feat(prior-art): edit-time record-sync nudge — the sync class (#2708)

A snippet recorded AT the exact file being edited is not a reuse
suggestion — it IS the record of the file being changed. The write-path
hint now renders those as their own SYNC class: 'snippet #N records this
file — updating the record is part of the edit (update_snippet /
verify_snippet)'. Nearby and semantic hits stay the reuse menu.

The two classes dedup on separate per-session channels (exclude_ids vs
exclude_sync_ids, .ids vs .sync.ids in the hook), so a reuse hint shown
early in a session can no longer silence the record-sync nudge when the
recorded file itself is edited later. Sync surfacing is measured under
its own note_usage source (write_path_sync) — its pull-through rate is
the scoreboard for whether edit-time sync actually happens, per decision
#2707 (no forge connection; records stay current in the session that has
the context). Plugin 0.1.31.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/scribe/routes/plugin.py

@@ -120,7 +120,13 @@ async def write_path_prior_art():
                              is NOT used as the location `repo` filter — see the
                              service docstring for why those two differ.
         project_id (opt)   — explicit project scope override (ad-hoc/testing).
-        exclude_ids (opt)  — comma-separated ids already surfaced this session.
+        exclude_ids (opt)  — comma-separated REUSE-class ids already surfaced
+                             this session.
+        exclude_sync_ids (opt) — comma-separated SYNC-class ids (snippets
+                             recorded AT the edited file, #2708) already
+                             surfaced. A separate channel on purpose: a reuse
+                             hint shown early must not suppress the record-sync
+                             nudge when the recorded file is edited later.
     """
     path = (request.args.get("path") or "").strip()
     code = request.args.get("code") or ""
@@ -139,9 +145,14 @@ async def write_path_prior_art():
         int(p) for p in (request.args.get("exclude_ids") or "").split(",")
         if p.strip().isdigit()
     ]
+    exclude_sync_ids = [
+        int(p) for p in (request.args.get("exclude_sync_ids") or "").split(",")
+        if p.strip().isdigit()
+    ]
 
     result = await plugin_ctx_svc.build_write_path_hint(
-        g.user.id, path, code=code, project_id=project_id, exclude_ids=exclude_ids
+        g.user.id, path, code=code, project_id=project_id,
+        exclude_ids=exclude_ids, exclude_sync_ids=exclude_sync_ids,
     )
     return jsonify(result)