feat(mcp): replace briefing tools with journal tools

The MCP was still calling /api/briefing/* endpoints I deleted in the
journal hard-cut. Replaced the briefing tool surface with a journal
equivalent so external MCP clients can inspect and control the journal
the same way they could the briefing.

Changes:
- New fable_mcp/tools/journal.py — helpers for /api/journal/* endpoints
- Delete fable_mcp/tools/briefing.py — RSS endpoints are gone too
- server.py: drop fable_list_rss_feeds, fable_add_rss_feed, fable_remove_rss_feed,
  fable_list_briefings, fable_get_today_briefing, fable_get_briefing_messages,
  fable_trigger_briefing, fable_reset_today_briefing
- server.py: add fable_get_today_journal, fable_get_journal_day,
  fable_list_journal_days, fable_trigger_journal_prep, fable_get_journal_config,
  fable_list_moments
- server.py: fable_get_conversation now points at journal.get_conversation
  (same /api/chat/conversations/{id} endpoint, just lives under journal helpers)
- Update _INSTRUCTIONS to describe the journal model (replacing the RSS/briefing
  section) — explains the daily prep, moments, day payloads
- Update top-line docstring: "Fable Assistant" → "Fable Scribe"

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

fable-mcp/fable_mcp/tools/journal.py

@@ -0,0 +1,96 @@
+"""MCP tools for inspecting and controlling the Fable Scribe Journal."""
+from __future__ import annotations
+
+from typing import Any
+
+from fable_mcp.client import FableClient
+
+
+# ── Day payloads ─────────────────────────────────────────────────────────────
+
+
+async def get_today_journal(client: FableClient) -> dict[str, Any]:
+    """Fetch today's journal day payload (creates today's conversation + prep if needed)."""
+    return await client.get("/api/journal/today")
+
+
+async def get_journal_day(client: FableClient, *, iso_date: str) -> dict[str, Any]:
+    """Fetch a specific day's journal payload by ISO date (YYYY-MM-DD)."""
+    return await client.get(f"/api/journal/day/{iso_date}")
+
+
+async def list_journal_days(client: FableClient) -> dict[str, Any]:
+    """List dates that have journal content for the current user."""
+    return await client.get("/api/journal/days")
+
+
+# ── Daily prep ───────────────────────────────────────────────────────────────
+
+
+async def trigger_journal_prep(
+    client: FableClient,
+    *,
+    iso_date: str | None = None,
+) -> dict[str, Any]:
+    """Force-regenerate the daily prep for today (or a specific day)."""
+    payload: dict[str, Any] = {}
+    if iso_date:
+        payload["date"] = iso_date
+    return await client.post("/api/journal/trigger-prep", json=payload)
+
+
+# ── Config ───────────────────────────────────────────────────────────────────
+
+
+async def get_journal_config(client: FableClient) -> dict[str, Any]:
+    """Fetch the user's journal config (prep schedule, day rollover, locations, etc.)."""
+    return await client.get("/api/journal/config")
+
+
+# ── Moments ──────────────────────────────────────────────────────────────────
+
+
+async def list_moments(
+    client: FableClient,
+    *,
+    query: str | None = None,
+    person_id: int | None = None,
+    place_id: int | None = None,
+    tag: str | None = None,
+    date_from: str | None = None,
+    date_to: str | None = None,
+    pinned_only: bool = False,
+    limit: int = 50,
+) -> dict[str, Any]:
+    """List/search journal moments with optional filters.
+
+    All params are optional. Returns a dict with a ``moments`` array.
+    """
+    params: dict[str, str] = {"limit": str(limit)}
+    if query:
+        params["query"] = query
+    if person_id is not None:
+        params["person_id"] = str(person_id)
+    if place_id is not None:
+        params["place_id"] = str(place_id)
+    if tag:
+        params["tag"] = tag
+    if date_from:
+        params["date_from"] = date_from
+    if date_to:
+        params["date_to"] = date_to
+    if pinned_only:
+        params["pinned_only"] = "true"
+    return await client.get("/api/journal/moments", params=params)
+
+
+# ── Generic conversation access (still works for journal conversations) ───────
+
+
+async def get_conversation(
+    client: FableClient,
+    *,
+    conversation_id: int,
+) -> dict[str, Any]:
+    """Fetch any conversation (chat or journal) with its full message list."""
+    return await client.get(f"/api/chat/conversations/{conversation_id}")