Mobile Phase 8h: Grid detail stage/reminder cards + Open-in-Grid deep-link

Grid full-screen investor detail, conformed to the dc anatomy:
- G4: pipeline stage as a single tappable .detail-tap-card (chip + Change/Add)
- G5: dedicated Reminder card fed by the soonest active reminder; tri-state
  (loading → disabled "Checking…" so a pre-load tap can't POST a duplicate;
  none → "No reminder set"; object → edit). Edits PATCH in place, else POST.
- G6 (notes timeline) was already in place.

Open-in-Grid deep-link, now on all three mobile detail surfaces (Contacts,
Pipeline, Reminders): a shared shell openInvestorInGrid(rowId) sets a one-shot
gridUiAction object the mobile grid consumes on mount to open that investor's
detail; the desktop grid drains the unrecognized object so it can't linger.
Each surface gets its grid row id from a server-injected source_row_id:
contacts via contact_grid_signals, opportunities via the durable
fundraising_investor_id join, reminders via the investor_id join. All are
read-only/GET-only or field-allowlist writes, so none need a strip point.

Tests: source_row_id injection assertions for contacts, opportunities, and
reminders; full suite 40/40. Client surfaces jsdom-verified.

backend/server.py

@@ -1917,7 +1917,10 @@ def contact_grid_signals(conn, contact_id=None):
         # highest-committed one (its stage + priority) so the signals reflect the strongest link.
         if prev is None or committed > prev['committed']:
             out[cid] = {'committed': committed, 'pipeline_stage': stage_by_srid.get(str(r['srid'] or '')),
-                        'priority': bool(r['priority'])}
+                        'priority': bool(r['priority']),
+                        # None (not '') when unset, matching the caller's `... if sig else None`;
+                        # source_row_id is NOT NULL on real investors so this is belt-and-suspenders.
+                        'source_row_id': str(r['srid']) if r['srid'] else None}
     return out
 
 
@@ -2718,14 +2721,16 @@ class CRMHandler(BaseHTTPRequestHandler):
 
         contacts = rows_to_list(conn.execute(query, args).fetchall())
         # Enrich with read-only, live-derived grid signals (committed → existing-LP avatar ring,
-        # pipeline_stage → stage pill) for the mobile Contacts card. Harmless extra fields for the
-        # desktop page, which ignores them. Never persisted on the contact (the list is read-only).
+        # pipeline_stage → stage pill, source_row_id → the detail's "Open investor in Grid"
+        # deep-link target) for the mobile Contacts card. Harmless extra fields for the desktop
+        # page, which ignores them. Never persisted on the contact (the list is read-only).
         signals = contact_grid_signals(conn)
         for c in contacts:
             sig = signals.get(str(c.get('id') or ''))
             c['committed'] = sig['committed'] if sig else 0
             c['pipeline_stage'] = sig['pipeline_stage'] if sig else None
             c['priority'] = bool(sig['priority']) if sig else False
+            c['source_row_id'] = sig['source_row_id'] if sig else None
         conn.close()
 
         return self.send_json({
@@ -2764,12 +2769,13 @@ class CRMHandler(BaseHTTPRequestHandler):
         ).fetchall())
 
         # Same read-only grid signals the list injects (committed → existing-LP ring/pill,
-        # pipeline_stage → stage pill), so the mobile detail sheet can render them without a
-        # second round-trip. Derived live; never stored on the contact.
+        # pipeline_stage → stage pill, source_row_id → "Open investor in Grid" deep-link), so the
+        # mobile detail sheet can render them without a second round-trip. Derived live; never stored.
         sig = contact_grid_signals(conn, contact_id).get(contact_id)
         result['committed'] = sig['committed'] if sig else 0
         result['pipeline_stage'] = sig['pipeline_stage'] if sig else None
         result['priority'] = bool(sig['priority']) if sig else False
+        result['source_row_id'] = sig['source_row_id'] if sig else None
 
         conn.close()
         return self.send_json({"data": result})
@@ -3015,12 +3021,14 @@ class CRMHandler(BaseHTTPRequestHandler):
         query = """
             SELECT op.*, c.first_name, c.last_name, c.email as contact_email,
                    o.name as organization_name, u.full_name as owner_name,
+                   fi.source_row_id as source_row_id,  -- the fundraising_investors row id (opportunities has no such column)
                    (SELECT MAX(communication_date) FROM communications
                      WHERE contact_id = op.contact_id AND deleted_at IS NULL) as last_contact_date
             FROM opportunities op
             LEFT JOIN contacts c ON op.contact_id = c.id
             LEFT JOIN organizations o ON op.organization_id = o.id
             LEFT JOIN users u ON op.owner_id = u.id
+            LEFT JOIN fundraising_investors fi ON fi.id = op.fundraising_investor_id
             WHERE 1=1 AND op.deleted_at IS NULL
         """
         args = []
@@ -3055,6 +3063,9 @@ class CRMHandler(BaseHTTPRequestHandler):
         # committed > 0), so card earmark and detail pill agree. Derived on GET, never persisted;
         # opportunity writes use a field allowlist (handle_update_opportunity) so it can't round-trip.
         # `last_contact_date` (subselect above) drives the card recency line + the Staleness sort.
+        # `source_row_id` (joined above via the durable fundraising_investor_id, not the contact path)
+        # is the 8h "Open investor in Grid" deep-link target for the Pipeline detail; null for an opp
+        # not linked to a grid investor (a legacy/manual deal).
         signals = contact_grid_signals(conn)
         for op in opps:
             sig = signals.get(str(op.get('contact_id') or ''))
@@ -3790,10 +3801,14 @@ class CRMHandler(BaseHTTPRequestHandler):
         conn = get_db()
         try:
             rows = conn.execute(
-                "SELECT r.*, ua.username AS assignee_name, uc.username AS creator_name "
+                # fi.source_row_id (joined via the reminder's investor_id) is the 8h "Open investor
+                # in Grid" deep-link target for the Reminders edit sheet; null for an unlinked reminder.
+                "SELECT r.*, ua.username AS assignee_name, uc.username AS creator_name, "
+                "fi.source_row_id AS source_row_id "
                 "FROM reminders r "
                 "LEFT JOIN users ua ON ua.id = r.assignee_id "
                 "LEFT JOIN users uc ON uc.id = r.created_by "
+                "LEFT JOIN fundraising_investors fi ON fi.id = r.investor_id "
                 "WHERE " + " AND ".join(where) +
                 # dated reminders first (soonest due), then undated by recency
                 " ORDER BY (r.due_date IS NULL OR r.due_date = ''), r.due_date ASC, r.created_at ASC",