feat(mcp): make Scribe reflexively recall + scope reads to the active project

The MCP surface advertised writing well but recall poorly, and project
scoping had no anchor that survived past enter_project's snapshot:

- search / list_notes dropped the project_id their services already
  support, so a scoped search was impossible — every query swept all
  projects and bled unrelated work into the session.
- The tool descriptions were mechanical ("Semantic search over the
  user's notes and tasks") with no trigger telling Claude WHEN to reach
  for them; the server instructions were all write-discipline and said
  nothing about searching before answering or starting work.

Changes:
- search, list_notes: add project_id param, wired to the service.
- search, list_notes, list_tasks: trigger-worded descriptions that push
  passing the active project's id and reserve project_id=0 for a
  deliberate cross-project sweep.
- _INSTRUCTIONS: add a 'Reach for Scribe to RECALL, not just to record'
  block — search before answering/starting, check for an existing ticket
  before create_task, scope reads to the active project (which does not
  stick on the server).

Paired with always-on rule #75 in the FabledSword-family rulebook.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/scribe/mcp/tools/notes.py

@@ -23,6 +23,7 @@ async def list_notes(
     offset: int = 0,
     tag: str = "",
     search_text: str = "",
+    project_id: int = 0,
 ) -> dict:
     """List notes (non-task documents) stored in Scribe.
 
@@ -30,6 +31,12 @@ async def list_notes(
     search against title and body. Results are ordered by last-updated descending.
 
     Use search for semantic/meaning-based lookup instead of exact keyword search.
+
+    Args:
+        project_id: Scope to one project. PASS THE ACTIVE PROJECT'S ID whenever a
+            project is in scope so you list that project's notes, not every
+            project's. 0 = no filter (all projects — use only for a deliberate
+            cross-project view).
     """
     uid = current_user_id()
     rows, total = await notes_svc.list_notes(
@@ -37,6 +44,7 @@ async def list_notes(
         q=search_text or None,
         tags=[tag] if tag else None,
         is_task=False,
+        project_id=project_id or None,
         limit=max(1, min(limit, 100)),
         offset=max(0, offset),
     )