docs(6205): task_logs, task_claims, reply_shapes, design_starter_roles, db_maintenance_scheduler comments drop citations and incident stories

- db_maintenance_scheduler states the storage-stall hazard the startup
  timeout guards, without the dated outage.
- design_starter_roles states why a missing role produces literals, without
  the call-site count, the operator's call date or a project's name.
- The rest drop milestone/step labels and record citations.

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

src/scribe/services/task_claims.py

@@ -1,4 +1,4 @@
-"""A task's claim — which session is working it right now (milestone 381 step 2).
+"""A task's claim — which session is working it right now.
 
 `status` says where THE WORK stands and is durable: `in_progress` means
 committed to, not finished. It cannot also say "someone is on this now",
@@ -38,7 +38,7 @@ if TYPE_CHECKING:
 # session gone overnight reads as gone. The cost either way is stated rather
 # than hidden: readers show the age beside `live`, never the boolean alone.
 #
-# NOT A SETTING, deliberately (#4385 weighed it). Settings are per user, and a
+# NOT A SETTING, deliberately. Settings are per user, and a
 # claim is read by everyone who can see the task: a per-user lease would make
 # one shared task read as live to one collaborator and dead to another, and
 # "is anyone on this?" only means something if every reader gets the same
@@ -131,9 +131,9 @@ async def bind_session(user_id: int, task_id: int, session_id: str) -> dict | No
         return claim_state(note, now)
 
 
-# --- The readers (milestone 381 step 3) ---------------------------------------
+# --- The readers --------------------------------------------------------------
 #
-# A claim nobody reads is the state before this milestone. SessionStart is the
+# A claim nobody reads is worth nothing. SessionStart is the
 # reader that pays rent to the session that set it, and it branches on the
 # `source` the host sends, because the same claim means different things
 # depending on what just happened to the context:
@@ -290,7 +290,7 @@ async def claims_for_session_start(
 
 
 async def release_session(user_id: int, session_id: str) -> int:
-    """Release every claim the caller holds under `session_id` (milestone 381 step 4).
+    """Release every claim the caller holds under `session_id`.
 
     Called by the plugin's SessionEnd hook: the session's context is about to
     stop existing, so the attention its claims record is ending too. A TIDY-UP,