feat(fusion_plating_shopfloor): /fp/tablet/unlock with per-user lockout (P6.1.3)

Verifies PIN, resets failure counter on success, increments + locks out
on 5 consecutive failures (configurable via ir.config_parameter
fp.shopfloor.tablet_pin_fail_threshold + tablet_pin_fail_lockout_minutes,
both defaulting to 5).

Returns informative payloads:
  ok=true            current_tech_id, current_tech_name
  needs_setup=true   user has no PIN yet
  locked_until       lockout in effect (rejects even correct PIN)
  attempts_remaining failed but not yet locked

Logs INFO on success, WARNING on failure (with running counter +
locked flag).

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

fusion_plating/fusion_plating_shopfloor/controllers/tablet_controller.py

@@ -75,3 +75,75 @@ class FpTabletController(http.Controller):
             target.id, env.uid,
         )
         return {'ok': True}
+
+    # ======================================================================
+    # /fp/tablet/unlock — verify PIN + manage failure counter / lockout
+    # ======================================================================
+    @http.route('/fp/tablet/unlock', type='jsonrpc', auth='user')
+    def unlock(self, user_id, pin):
+        env = request.env
+        Users = env['res.users'].sudo()  # need sudo to read hash field
+        target = Users.browse(int(user_id))
+        if not target.exists():
+            return {'ok': False, 'error': _('User not found.')}
+
+        # No PIN set yet — caller must set one first
+        if not target.x_fc_tablet_pin_hash:
+            return {
+                'ok': False,
+                'error': _('No PIN set. Set one in Preferences first.'),
+                'needs_setup': True,
+            }
+
+        # Currently locked out?
+        now = fields.Datetime.now()
+        if target.x_fc_tablet_locked_until and target.x_fc_tablet_locked_until > now:
+            return {
+                'ok': False,
+                'error': _('Account locked. Try again in a few minutes.'),
+                'locked_until': target.x_fc_tablet_locked_until.isoformat(),
+            }
+
+        if target.verify_tablet_pin(pin):
+            # Reset failure state on success
+            target.write({
+                'x_fc_tablet_pin_failed_count': 0,
+                'x_fc_tablet_locked_until': False,
+            })
+            _logger.info(
+                "Tablet unlocked by uid %s (session uid %s)",
+                target.id, env.uid,
+            )
+            return {
+                'ok': True,
+                'current_tech_id': target.id,
+                'current_tech_name': target.name,
+            }
+
+        # Wrong PIN — increment and check threshold
+        new_count = (target.x_fc_tablet_pin_failed_count or 0) + 1
+        threshold = int(env['ir.config_parameter'].sudo().get_param(
+            'fp.shopfloor.tablet_pin_fail_threshold', 5,
+        ))
+        lockout_min = int(env['ir.config_parameter'].sudo().get_param(
+            'fp.shopfloor.tablet_pin_fail_lockout_minutes', 5,
+        ))
+        vals = {'x_fc_tablet_pin_failed_count': new_count}
+        if new_count >= threshold:
+            vals['x_fc_tablet_locked_until'] = now + timedelta(minutes=lockout_min)
+        target.write(vals)
+        _logger.warning(
+            "Tablet PIN failure for uid %s (count=%d, locked=%s)",
+            target.id, new_count, bool(vals.get('x_fc_tablet_locked_until')),
+        )
+        if vals.get('x_fc_tablet_locked_until'):
+            return {
+                'ok': False,
+                'error': _('Too many failed attempts. Locked for %d minutes.') % lockout_min,
+                'locked_until': vals['x_fc_tablet_locked_until'].isoformat(),
+            }
+        return {
+            'ok': False,
+            'error': _('Incorrect PIN.'),
+            'attempts_remaining': threshold - new_count,
+        }