feat(dashboard): technician performance report + real technician names

Wahab customer request (relay #748 v3 next-wave).

3a. Fix 'Tech #N' display:
- FM dashboard's "Technician Workload" card was built from
  `Tech #${t.assigned_to}`; it now reads Ticket.assigned_technician_name
  (falling back to 'Unassigned', matching /tickets).
- Template sweep confirms no other `Tech #` placeholder exists.

3b. Technician performance dashboard:
- New bearer-gated GET /api/tickets/tech-performance aggregating existing
  ticket columns only (no schema change): per-technician total assigned,
  completed, in progress, escalated, cancelled, pending, open tasks,
  completion rate, and created_at -> closed_at resolution time with explicit
  counts for finished tasks lacking a timestamp. Rows key on user id so
  same-name technicians stay separate; labels are real names. Fleet totals
  and an unassigned-ticket count are included.
- New /dashboard/tech-performance page (FM + CEO nav and links) with sortable
  table, completion bars and empty states; same-origin vendored assets only.
- Bucket map, service, schemas and tests in app/services/ticket.py,
  app/schemas/ticket.py, tests/test_tech_performance.py.

Tests: 111 passed (101 existing + 10 new).

AGENTS.md

@@ -89,6 +89,7 @@ number. Covered by `tests/test_whatsapp_demo_number.py`.
 | GET | `/dashboard/cs` | Client | CS dashboard |
 | GET | `/dashboard/fm` | Client | FM dashboard |
 | GET | `/dashboard/ceo` | Client | CEO dashboard |
+| GET | `/dashboard/tech-performance` | Client | Technician performance report (FM + CEO nav) |
 | GET | `/tickets` | Client | All Issues filterable table |
 | GET | `/tickets/new` | Client | Create Issue form |
 | GET | `/tickets/{id}` | Client | Issue detail with timeline |
@@ -96,6 +97,20 @@ number. Covered by `tests/test_whatsapp_demo_number.py`.
 Frontend: Alpine.js + Tailwind CSS vendored same-origin (no CDN) — see
 "Frontend assets" below. Auth state in localStorage. Role-based nav routing in `base.html`.
 
+### Technician performance (Wahab request)
+`GET /api/tickets/tech-performance` (Bearer) aggregates per-technician workload/outcomes by
+**real name** using only existing ticket columns (`assigned_to`/`status`/`created_at`/`closed_at`
+→ `users.full_name`) — no schema change. Aggregation lives in
+`app/services/ticket.py::get_technician_performance`; bucket map `_TECH_STATUS_BUCKETS` defines
+`completed` (Completed/Closed), `in_progress`, `escalated`, `cancelled`, and `pending` (remainder),
+so the buckets always sum to `total_assigned`. `completion_rate = completed/total_assigned`;
+`avg_resolution_hours` averages `created_at → closed_at` only where `closed_at` is set, with
+`resolved_without_timestamps` counting finished tasks that lack one. Rows key on user id (same-name
+techs stay separate), sorted completed desc → workload → name. UI:
+`app/templates/dashboard/tech-performance.html`, linked from FM + CEO nav and the FM
+"Technician Workload" card — that card reads `Ticket.assigned_technician_name`, never an id
+placeholder. Regression: `tests/test_tech_performance.py`.
+
 ### Frontend assets (vendored, LAN-safe)
 - Alpine.js 3.17.2 + Tailwind Play 3.4.17 are committed under `app/static/vendor/`
   and served at `/static/vendor/…` (mounted in `app/main.py`, versioned