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/models/note.py

@@ -76,7 +76,7 @@ class Note(Base, TimestampMixin, SoftDeleteMixin):
     recurrence_next_spawn_at: Mapped[datetime | None] = mapped_column(
         DateTime(timezone=True), nullable=True
     )
-    # The claim — which session is working this task NOW (milestone 381).
+    # The claim — which session is working this task NOW.
     # Orthogonal to `status`: status is the work's state and durable, the claim
     # is a session's attention and dies on read once `claim_touched_at` is past
     # the lease. Semantics in services/task_claims.py.
@@ -93,7 +93,7 @@ class Note(Base, TimestampMixin, SoftDeleteMixin):
     #   snippet — a reusable shape, with its structured fields mirrored in
     #             `data` and its trigger composed into the title (0070)
     #   lesson  — a transferable insight, findable by WHEN IT APPLIES rather
-    #             than by topic (milestone 385). Same mirror discipline as a
+    #             than by topic. Same mirror discipline as a
     #             snippet: the trigger lives in `data.when_to_apply` and is
     #             composed into the title and the head of the body, which is
     #             what puts it in the embedded document. A lesson is never a
@@ -102,8 +102,8 @@ class Note(Base, TimestampMixin, SoftDeleteMixin):
     #
     # DELIBERATELY UNGATED. Unlike `task_kind` there is no CHECK on this column:
     # migration 0036 added it as plain Text with a server default and nothing
-    # has constrained it since, so rule 36 has no whitelist to expand when a
-    # kind is added. The vocabulary that actually decides what a reader can
+    # has constrained it since, so there is no whitelist to expand when a kind
+    # is added. The vocabulary that actually decides what a reader can
     # reach is `services.knowledge._FACETS`; an unrecognised value there
     # resolves to a filter matching nothing, which is the intended answer to a
     # typo.
@@ -117,7 +117,7 @@ class Note(Base, TimestampMixin, SoftDeleteMixin):
     #            so historical plan-tasks stay writable
     # Only meaningful when the note is a task (status is not None); ordinary
     # notes keep the 'work' default and ignore it. Orthogonal to note_type
-    # (which is the note/entity axis). CHECK notes_task_kind_check (rule 36).
+    # (which is the note/entity axis). CHECK notes_task_kind_check.
     task_kind: Mapped[str] = mapped_column(Text, default="work", server_default="work")
     # Queryable structured fields for typed records — currently snippets, whose
     # name/language/signature/locations live here so they can be INDEXED. The