feat(500): the reply shapes become server product content - a compact core and per-kind slices, each tied to its moment (#5493)

services/reply_shapes.py is the single source of the default reply shapes:
the core (every reply, ~1,800 chars against a 2,200 budget) and three
slices - completion on work.finish, asks on reply.ask, plan on work.plan.
Read through list_reply_shapes (MCP, read-only) and GET
/api/retrieval/reply-shapes, one service behind both doors.

Nothing delivers them yet; that is step 3. The skill still carries its
copy until step 4 shrinks it to the long-form reference.

The software-only vocabulary guard moves into tests/helpers.py
(DEV_ONLY, dev_only_hits) rather than becoming a fourth copy.

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

tests/test_routes_retrieval_tuning.py

@@ -46,6 +46,7 @@ def test_every_endpoint_is_reachable_on_the_app():
         "/api/retrieval/moments/mappings",
         "/api/retrieval/moments/proposals",
         "/api/retrieval/moments/proposals/judge",
+        "/api/retrieval/reply-shapes",
     }