feat(moments): actions map onto moments, with in-session corrections (milestone 458 step 2, #4920)

moment_actions.resolve(tool, input) names every moment a call reaches and
the action that reached it. One call can reach several: kubectl apply is
a run, a deliver and a reach outside the workspace. Command tools match by
how each segment of the line starts, with a word boundary; other tools by
field=value arguments. The MCP server prefix and case are ignored.

56 shipped defaults cover the harness tools, Scribe tools and common
command shapes. moment_mappings (migration 0116) holds what an install
adds and the defaults it switches off. A removal is a stored row, so an
upgrade does not switch the default back on.

Per the operator ruling, corrections happen in the session: map_action
and unmap_action (write tools) return now_reaches so the fix can be
confirmed in the same reply. list_moments now shows each moment's
actions on this install. REST mirrors both doors, recorded as human.
Backup v21 carries the mappings.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/scribe/services/moment_actions.py

@@ -0,0 +1,393 @@
+"""Which actions reach which moment: shipped defaults plus each install's own (milestone 458 step 2).
+
+The catalog (`services/moments.py`) says what the moments ARE. This module says
+how the work gets there. One call can reach several moments: `kubectl apply`
+is a run, a deliver and a reach outside the workspace all at once, and a rule
+mounted on any of them should arrive.
+
+AN ACTION is a tool plus an optional `match`:
+
+- `match` empty — every call of that tool (`Edit` → work.change).
+- A tool that runs a command (its input carries `command`) — how the command
+  starts, tested against each segment of a compound line, so
+  `cd app && make ship` reaches what `make ship` reaches. Leading `VAR=value`
+  assignments are skipped; a word boundary is required, so `git push` does
+  not match `git pushd`.
+- Any other tool — `field=value` pairs, comma-separated, all of which must
+  hold (`update_task` with `status=done`).
+
+Tool names are compared without any MCP server prefix and without case:
+`mcp__plugin_x__update_task` and `update_task` are one tool, because what an
+install called its server is not something a mapping should depend on.
+
+WHY THE DEFAULTS ARE CODE AND THE CORRECTIONS ARE ROWS
+
+The defaults cover the actions every install shares — the harness's own tools,
+Scribe's own tools, the commonest command shapes. They ship, and improve, with
+the product. What no default can know is how one operator works, so an install
+ADDS mappings and REMOVES defaults that misfire for it, in-session, through
+`map_action` / `unmap_action`. A removal is stored rather than applied to the
+defaults so it survives an upgrade that ships the same default again.
+
+The concrete commands below are examples of reaching a moment, which is why
+they may name particular tools when the moments themselves may not.
+"""
+from __future__ import annotations
+
+import logging
+import re
+from dataclasses import dataclass
+from typing import Iterable
+
+from sqlalchemy import select
+
+from scribe.models import async_session
+from scribe.models.moment_mapping import MomentMapping
+from scribe.services import moments as catalog
+
+logger = logging.getLogger(__name__)
+
+ADD, REMOVE = "add", "remove"
+EFFECTS = (ADD, REMOVE)
+DEFAULT, INSTALL = "default", "install"
+
+# The input field that makes a tool a command-runner, and the tools known to
+# be one. The field drives MATCHING (any tool whose call carries a command is
+# matched by prefix); the names drive VALIDATION, so a prefix-style match on a
+# tool that takes no command is refused rather than stored to never fire.
+COMMAND_FIELD = "command"
+COMMAND_TOOLS = frozenset({"bash"})
+
+# The harness's skill loader: loading a procedure reaches `skill.<its name>`,
+# derived from the call rather than listed, since the names are the
+# procedures' own.
+SKILL_TOOL, SKILL_FIELD = "skill", "skill"
+
+_SEGMENT_SPLIT = re.compile(r"&&|\|\||[;|\n]")
+_ENV_ASSIGN = re.compile(r"^[A-Za-z_][A-Za-z0-9_]*=\S*\s+")
+
+
+@dataclass(frozen=True)
+class Action:
+    tool: str
+    match: str
+    moment: str
+
+
+def _defaults() -> tuple[Action, ...]:
+    out: list[Action] = []
+
+    def on(moment: str, tool: str, *matches: str) -> None:
+        for m in matches or ("",):
+            out.append(Action(tool, m, moment))
+
+    # The harness's own tools.
+    on("work.change", "Edit")
+    on("work.change", "Write")
+    on("work.change", "MultiEdit")
+    on("work.change", "NotebookEdit")
+    on("work.run", "Bash")
+    on("work.delegate", "Task")
+    on("work.delegate", "Agent")
+    on("work.plan", "EnterPlanMode")
+    on("work.plan", "ExitPlanMode")
+    on("reply.ask", "AskUserQuestion")
+
+    # Scribe's own tools — every install has these, so their moments ship.
+    on("work.start", "update_task", "status=in_progress")
+    on("work.finish", "update_task", "status=done", "status=cancelled")
+    on("work.finish", "update_milestone", "status=done")
+    on("work.plan", "start_planning")
+    on("work.plan", "create_milestone")
+    for tool in ("create_note", "create_lesson", "create_rule",
+                 "create_project_rule", "create_preference", "create_snippet",
+                 "create_process"):
+        on("work.record", tool)
+
+    # The commonest command shapes. An install's own (`make ship`,
+    # `./deploy.sh`) are what map_action is for.
+    on("work.deliver", "Bash",
+       "git push", "git merge", "gh pr merge", "gh release create",
+       "docker push", "kubectl apply", "helm install", "helm upgrade",
+       "terraform apply", "npm publish", "twine upload", "cargo publish")
+    on("work.verify", "Bash",
+       "pytest", "python -m pytest", "npm test", "npm run test", "yarn test",
+       "pnpm test", "go test", "go vet", "cargo test", "make test",
+       "make check", "ruff check", "mypy", "terraform plan",
+       "terraform validate")
+    on("env.reach", "Bash",
+       "ssh", "scp", "curl", "wget", "kubectl", "helm")
+    return tuple(out)
+
+
+DEFAULT_ACTIONS: tuple[Action, ...] = _defaults()
+
+
+# ── matching ──────────────────────────────────────────────────────────────
+
+def tool_key(name: str) -> str:
+    """The tool's bare, lowercased name: no MCP server prefix."""
+    clean = (name or "").strip()
+    if clean.startswith("mcp__"):
+        clean = clean.rsplit("__", 1)[-1]
+    return clean.lower()
+
+
+def _squash(text: str) -> str:
+    return " ".join((text or "").split())
+
+
+def _segments(command: str) -> list[str]:
+    out = []
+    for part in _SEGMENT_SPLIT.split(command or ""):
+        seg = part.strip().lstrip("(").strip()
+        while _ENV_ASSIGN.match(seg):
+            seg = _ENV_ASSIGN.sub("", seg, count=1)
+        seg = _squash(seg)
+        if seg:
+            out.append(seg)
+    return out
+
+
+def _pairs(match: str) -> dict[str, str] | None:
+    """`a=b, c=d` → {"a": "b", "c": "d"}; None when it is not that shape."""
+    out: dict[str, str] = {}
+    for part in (match or "").split(","):
+        key, sep, value = part.partition("=")
+        if not sep or not key.strip():
+            return None
+        out[key.strip().lower()] = value.strip().lower()
+    return out or None
+
+
+def action_matches(action: Action, tool: str, tool_input: dict | None) -> bool:
+    if tool_key(action.tool) != tool_key(tool):
+        return False
+    if not action.match:
+        return True
+    tool_input = tool_input or {}
+    command = tool_input.get(COMMAND_FIELD)
+    if isinstance(command, str):
+        want = _squash(action.match)
+        return any(seg == want or seg.startswith(want + " ")
+                   for seg in _segments(command))
+    pairs = _pairs(action.match)
+    if pairs is None:
+        return False
+    given = {str(k).lower(): v for k, v in tool_input.items()}
+    return all(
+        str(given.get(k, "")).strip().lower() == v for k, v in pairs.items()
+    )
+
+
+def effective_actions(mappings: Iterable) -> list[tuple[Action, str]]:
+    """The defaults this install has not removed, then its own additions.
+
+    `mappings` are MomentMapping rows, or anything with the same four fields.
+    """
+    removed: set[tuple[str, str, str]] = set()
+    added: list[Action] = []
+    for m in mappings:
+        key = (tool_key(m.tool), _squash(m.match), m.moment)
+        if m.effect == REMOVE:
+            removed.add(key)
+        elif m.effect == ADD:
+            added.append(Action(m.tool, _squash(m.match), m.moment))
+    out = [
+        (a, DEFAULT) for a in DEFAULT_ACTIONS
+        if (tool_key(a.tool), a.match, a.moment) not in removed
+    ]
+    out.extend((a, INSTALL) for a in added)
+    return out
+
+
+def resolve(tool: str, tool_input: dict | None, mappings: Iterable = ()) -> list[dict]:
+    """Every moment this call reaches, each with the action that reached it.
+
+    One entry per moment, in catalog order. When two actions reach the same
+    moment the more specific one — the longer match — is the one named, since
+    "reached by `git push`" says more than "reached by Bash".
+    """
+    best: dict[str, dict] = {}
+    for action, via in effective_actions(mappings):
+        if not action_matches(action, tool, tool_input):
+            continue
+        held = best.get(action.moment)
+        if held is None or len(action.match) > len(held["match"]):
+            best[action.moment] = {
+                "moment": action.moment, "tool": action.tool,
+                "match": action.match, "via": via,
+            }
+
+    if tool_key(tool) == SKILL_TOOL:
+        name = str((tool_input or {}).get(SKILL_FIELD) or "").strip().lower()
+        moment = catalog.SKILL_PREFIX + name
+        if name and catalog.is_moment(moment):
+            best[moment] = {"moment": moment, "tool": tool, "match": f"skill={name}",
+                            "via": DEFAULT}
+
+    order = {name: i for i, name in enumerate(catalog.MOMENTS)}
+    return sorted(best.values(), key=lambda h: (order.get(h["moment"], len(order)), h["moment"]))
+
+
+def _sample_input(tool: str, match: str) -> dict:
+    """A call that this action would describe — for reporting what it reaches."""
+    if not match:
+        return {}
+    if tool_key(tool) in COMMAND_TOOLS:
+        return {COMMAND_FIELD: match}
+    return dict(_pairs(match) or {})
+
+
+def _clean(tool: str, match: str, moment: str) -> tuple[str, str, str]:
+    """Validate a mapping's three parts, or refuse with what would work."""
+    bare = (tool or "").strip()
+    if bare.startswith("mcp__"):
+        bare = bare.rsplit("__", 1)[-1]
+    if not bare:
+        raise ValueError("tool is required — the tool as the harness names it, e.g. Bash or update_task")
+    clean_match = _squash(match)
+    if clean_match and tool_key(bare) not in COMMAND_TOOLS and _pairs(clean_match) is None:
+        raise ValueError(
+            f"{bare} does not run a command, so `match` names its arguments as "
+            f"field=value pairs (e.g. status=done), not {clean_match!r}. Leave "
+            f"it empty to map every {bare} call."
+        )
+    return bare, clean_match, catalog.require_moment(moment)
+
+
+def _is_default(tool: str, match: str, moment: str) -> bool:
+    return any(
+        tool_key(a.tool) == tool_key(tool) and a.match == match and a.moment == moment
+        for a in DEFAULT_ACTIONS
+    )
+
+
+# ── the install's own ─────────────────────────────────────────────────────
+
+async def list_mappings(user_id: int) -> list[MomentMapping]:
+    async with async_session() as session:
+        rows = await session.execute(
+            select(MomentMapping)
+            .where(MomentMapping.user_id == user_id)
+            .order_by(MomentMapping.id)
+        )
+        return list(rows.scalars().all())
+
+
+async def moments_for(user_id: int, tool: str, tool_input: dict | None) -> list[dict]:
+    """The moments a call reaches for this user.
+
+    Fails OPEN to the defaults: an unreadable mapping table must cost the
+    install its corrections, not every moment.
+    """
+    try:
+        mappings = await list_mappings(user_id)
+    except Exception:
+        logger.warning("moment mappings unreadable; using the defaults", exc_info=True)
+        mappings = []
+    return resolve(tool, tool_input, mappings)
+
+
+async def _find(session, user_id: int, tool: str, match: str, moment: str):
+    rows = await session.execute(
+        select(MomentMapping).where(
+            MomentMapping.user_id == user_id,
+            MomentMapping.moment == moment,
+            MomentMapping.match == match,
+        )
+    )
+    return next((r for r in rows.scalars().all() if tool_key(r.tool) == tool_key(tool)), None)
+
+
+async def _reaches(user_id: int, tool: str, match: str) -> list[dict]:
+    return resolve(tool, _sample_input(tool, match), await list_mappings(user_id))
+
+
+async def map_action(
+    user_id: int, tool: str, match: str, moment: str,
+    *, reason: str = "", actor: str = "model",
+) -> dict:
+    """Make an action reach a moment for this install.
+
+    Mapping a shipped default this install had removed restores it; mapping
+    one already in force changes nothing and says so.
+    """
+    tool, match, moment = _clean(tool, match, moment)
+    reason = (reason or "").strip()
+    async with async_session() as session:
+        row = await _find(session, user_id, tool, match, moment)
+        if _is_default(tool, match, moment):
+            if row is not None and row.effect == REMOVE:
+                await session.delete(row)
+                await session.commit()
+                change = "restored the shipped default"
+            else:
+                change = "already a shipped default — nothing to add"
+        elif row is not None:
+            row.reason = reason or row.reason
+            row.actor = actor
+            await session.commit()
+            change = "already mapped — reason updated" if reason else "already mapped"
+        else:
+            session.add(MomentMapping(
+                user_id=user_id, tool=tool, match=match, moment=moment,
+                effect=ADD, reason=reason, actor=actor,
+            ))
+            await session.commit()
+            change = "mapped"
+    return {
+        "change": change, "tool": tool, "match": match, "moment": moment,
+        "now_reaches": await _reaches(user_id, tool, match),
+    }
+
+
+async def unmap_action(
+    user_id: int, tool: str, match: str, moment: str,
+    *, reason: str = "", actor: str = "model",
+) -> dict:
+    """Stop an action reaching a moment for this install.
+
+    An install's own mapping is deleted. A shipped default is switched off by
+    a stored removal, so the next release does not switch it back on.
+    """
+    tool, match, moment = _clean(tool, match, moment)
+    reason = (reason or "").strip()
+    async with async_session() as session:
+        row = await _find(session, user_id, tool, match, moment)
+        if row is not None and row.effect == ADD:
+            await session.delete(row)
+            await session.commit()
+            change = "removed this install's mapping"
+        elif _is_default(tool, match, moment):
+            if row is None:
+                session.add(MomentMapping(
+                    user_id=user_id, tool=tool, match=match, moment=moment,
+                    effect=REMOVE, reason=reason, actor=actor,
+                ))
+                await session.commit()
+                change = "switched off the shipped default"
+            else:
+                change = "the shipped default was already off"
+        else:
+            raise ValueError(
+                f"nothing maps {tool}{' ' + repr(match) if match else ''} onto "
+                f"{moment}, so there is nothing to remove. list_moments shows "
+                f"which actions reach each moment."
+            )
+    return {
+        "change": change, "tool": tool, "match": match, "moment": moment,
+        "now_reaches": await _reaches(user_id, tool, match),
+    }
+
+
+async def actions_by_moment(user_id: int) -> dict:
+    """Each moment's actions in force, and the defaults this install removed."""
+    mappings = await list_mappings(user_id)
+    by_moment: dict[str, list[dict]] = {}
+    for action, via in effective_actions(mappings):
+        by_moment.setdefault(action.moment, []).append(
+            {"tool": action.tool, "match": action.match, "via": via}
+        )
+    removed = [m.to_dict() for m in mappings if m.effect == REMOVE]
+    return {"actions": by_moment, "removed_defaults": removed}