feat(moments): a mount that keeps arriving where it does not apply proposes its own removal (milestone 458 step 7b, #4955)

The open-after-moment signal proposes a mount; nothing proposed taking one
off, so a wrong mount was noise at every occurrence until someone happened
to notice. rule_misfired(rule_id, moment, why, reached_by) records a report
against a MOUNTED pair, counted per distinct day (the MCP door carries no
session id) on a new rule_moment_judgments.misfire column (migration 0119,
backup v24). At three days the response carries a line asking the agent to
offer the operator the fix - reject takes the rule off, unmap_action stops
the action reaching the moment, confirm keeps the mount and stops the
asking - and Settings > Moments lists it as an unmount proposal with the
reasons and the actions that reached it. A re-mount clears the count.

Taught in moments.md, missed-retrieval.md and the reply hold's wording.

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

src/scribe/services/lesson_rules.py

@@ -486,17 +486,19 @@ def situation_key(arm: str, text: str) -> str:
     """A fingerprint of one situation, so a repeat counts once.
 
     `arm` is part of the key — "p" for a prompt, "w" for a file being written,
-    "s" for a session (the rule↔moment signal, milestone 458 step 7) —
+    "s" for a session (the rule↔moment signal, milestone 458 step 7), "d"
+    for a day (the misfire signal, step 7b, whose door carries no session) —
     because each names a different kind of situation and must not collide.
     On the prompt arm the text is the prompt: lowercased, split into word
     tokens of _MIN_TOKEN or more, de-duplicated and sorted, so the same ask
     re-sent with different spacing, punctuation, case or word order is one
     situation. On the write arm the text is the PATH, not the code: every
     edit to one file is one situation, however much the code differs between
-    them. The session arm keys on the session id as given. Empty when there
-    is nothing to key on.
+    them. The session and day arms key on the id or date as given — a date's
+    "10" and "05" are shorter than _MIN_TOKEN, so tokenising it would make
+    every day of a year one situation. Empty when there is nothing to key on.
     """
-    if arm in ("w", "s"):
+    if arm in ("w", "s", "d"):
         basis = (text or "").strip()
     else:
         tokens = sorted({t for t in re.findall(r"[a-z0-9]+", (text or "").lower())