feat(fusion_plating_shopfloor): /fp/tablet/tiles + /fp/tablet/ping endpoints (P6.1.4-P6.1.5)

Tiles returns the lock-screen grid: operator-group users, sorted
clocked-in-first then alphabetical, with avatar URL + has_pin flag.
Honours station.x_fc_authorised_user_ids when non-empty (Phase 6.1.6
adds that field). Ping is a lightweight ack used by FpTabletLock as
a heartbeat — logs current_tech_id at DEBUG for forensic visibility.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

fusion_plating/fusion_plating_shopfloor/controllers/tablet_controller.py

@@ -147,3 +147,65 @@ class FpTabletController(http.Controller):
             'error': _('Incorrect PIN.'),
             'attempts_remaining': threshold - new_count,
         }
+
+    # ======================================================================
+    # /fp/tablet/tiles — lock-screen tile grid
+    # ======================================================================
+    @http.route('/fp/tablet/tiles', type='jsonrpc', auth='user')
+    def tiles(self, station_id=None):
+        env = request.env
+        op_group = env.ref(
+            'fusion_plating.group_fusion_plating_operator',
+            raise_if_not_found=False,
+        )
+        if not op_group:
+            return {'ok': False, 'error': 'operator group missing'}
+
+        # Determine candidate users — station roster wins if non-empty
+        users = op_group.user_ids
+        if station_id:
+            Station = env['fusion.plating.shopfloor.station']
+            station = Station.browse(int(station_id))
+            if (station.exists()
+                    and 'x_fc_authorised_user_ids' in station._fields
+                    and station.x_fc_authorised_user_ids):
+                users = station.x_fc_authorised_user_ids
+
+        # has_pin needs sudo-read on the hash field
+        clocked_ids = set()
+        if 'hr.employee' in env and hasattr(
+            env['hr.employee'], '_fp_clocked_in_user_ids',
+        ):
+            clocked_ids = env['hr.employee']._fp_clocked_in_user_ids() or set()
+
+        users_sorted = users.sorted('name')
+        users_sudo = users_sorted.sudo()
+        tiles = []
+        for u, u_sudo in zip(users_sorted, users_sudo):
+            tiles.append({
+                'user_id': u.id,
+                'name': u.name,
+                'avatar_url': f'/web/image/res.users/{u.id}/avatar_128',
+                'is_clocked_in': u.id in clocked_ids,
+                'has_pin': bool(u_sudo.x_fc_tablet_pin_hash),
+            })
+        # Clocked-in first, then alphabetical within bucket
+        tiles.sort(key=lambda t: (not t['is_clocked_in'], t['name']))
+        return {'ok': True, 'tiles': tiles}
+
+    # ======================================================================
+    # /fp/tablet/ping — heartbeat used by the OWL component on every action
+    # ======================================================================
+    @http.route('/fp/tablet/ping', type='jsonrpc', auth='user')
+    def ping(self, current_tech_id=None):
+        """Lightweight heartbeat. Used by the OWL component to confirm
+        the server-side session is alive AND to log the tech-of-record
+        every few minutes so the server has forensic visibility into
+        which tech was 'driving' the tablet at any moment.
+        """
+        if current_tech_id:
+            _logger.debug(
+                "Tablet ping: session uid %s carrying tablet_tech_id=%s",
+                request.env.uid, current_tech_id,
+            )
+        return {'ok': True, 'server_time': fields.Datetime.now().isoformat()}