email-activity agent: propose -> review -> approve grid notes (v0.1.0:64)

When a sent/received email is matched to an investor, a local-model agent drafts a
one-line dated note and queues it as a PENDING proposal (it never writes the grid
itself). On the Email Capture page a partner sees "Proposed grid notes", can edit the
text, and Approve (appends to that investor's grid notes cell, newest at bottom,
stamped with the approver) or Dismiss. Going-forward only: a cutoff (app_settings
email_activity_since, set on first run) means email dated before the feature was
enabled is never summarized, so the historical backfill makes no noise. Sovereign:
summaries run entirely on the local model (no redaction needed). Gmail sync interval
tightened 180 -> 15 min so outgoing email surfaces quickly.

Backend: migration 0002 (email_activity_proposals); propose_email_activity_notes()
runs via a new scheduler post_sync hook; list/decide functions + routes
GET /api/activity/proposals, POST .../{id}/approve|dismiss. Grid append stamps the
approving user (fundraising_state.updated_by has a FK to users). Test
test_email_activity.py (propose cutoff/idempotency, approve appends + edited note,
dismiss, already-decided guard) under FK enforcement.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/email_integration/scheduler.py

@@ -57,7 +57,10 @@ def _conn_factory_from_env() -> Callable[[], sqlite3.Connection]:
     return get_db
 
 
-def start_sync_scheduler(conn_factory: Optional[Callable] = None) -> None:
+def start_sync_scheduler(conn_factory: Optional[Callable] = None,
+                         post_sync: Optional[Callable] = None) -> None:
+    """Start the periodic Gmail sync loop. `post_sync`, if given, is called after each
+    sync pass (best-effort) — used to run the email-activity summarizer."""
     if _state["thread"] is not None:
         return  # already running
 
@@ -98,6 +101,11 @@ def start_sync_scheduler(conn_factory: Optional[Callable] = None) -> None:
             finally:
                 _state["running_now"] = False
                 _state["last_run"] = t0
+            if post_sync is not None:
+                try:
+                    post_sync()
+                except Exception:
+                    log.exception("post_sync hook failed; continuing")
             if stop.wait(_cfg.CONFIG.sync_interval_sec):
                 return