docs(6206): webhooks, search, rulebooks routes and retrieval_tuning, note, models/__init__ drop citations

routes/search states the derived-facets property rather than the silent
whole-corpus bug that motivated it; routes/rulebooks gives the preference
restore exception its reasoning without the milestone numbers it cited.

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

src/scribe/routes/rulebooks.py

@@ -280,19 +280,18 @@ async def get_rule_version(rule_id: int, version_id: int):
     return jsonify(version.to_dict(include_text=True))
 
 
-# NO restore route FOR A RULE, deliberately (milestone 323). A note version
+# NO restore route FOR A RULE, deliberately. A note version
 # can be restored; a binding instruction should not be revertible in one
 # click. Putting a rewrite back goes through update_rule, which takes its own
 # snapshot and leaves the undo in the history like any other edit — a silent
 # revert would erase the only record of why the rewrite happened.
 #
 # A PREFERENCE IS THE EXCEPTION, and the route below refuses anything else.
-# 323's reasoning turns on the rewrite being the operator's own decision.
+# The reasoning above turns on the rewrite being the operator's own decision.
 # A preference's rewrite is not: the agent makes it mid-work without asking,
 # which is what the kind is for. Reverting one is a veto over someone else's
-# edit rather than an undo of your own, and milestone 399 named the cost of
-# making that veto expensive — drift supervised in name only. The safeguard
-# 323 actually wanted survives intact, because the restore goes through
+# edit rather than an undo of your own, and making that veto expensive leaves
+# drift supervised in name only. The safeguard survives intact, because the restore goes through
 # update_rule too: the rewrite stays in the history with the revert recorded
 # after it, so the history gains an entry rather than losing one.
 
@@ -369,7 +368,7 @@ async def unrelate_rules(relation_id: int):
 @login_required
 async def move_rule(rule_id: int):
     """Give a rule a new home: {topic_id} makes it global, {project_id} makes
-    it that project's. The MCP twin is move_rule (rule 33: same names)."""
+    it that project's. The MCP twin is move_rule, under the same names."""
     data = await request.get_json() or {}
     uid = get_current_user_id()
     try:
@@ -452,7 +451,7 @@ async def create_project_rule(project_id: int):
     )), 201
 
 
-# ── The staleness sweep (milestone 312) ────────────────────────────────
+# ── The staleness sweep ────────────────────────────────────────────────
 
 @rulebooks_bp.get("/rules-due-for-verification")
 @login_required