fix: safe status-recommendation flow, MO-016 order independence, brand constant, message codes

- Add a single shared, pure vehicle-status evaluator (app/services/vehicle_status.py)
  used identically by the data-quality scanner, a new non-mutating status-recommendation
  preview endpoint, and a transactional apply endpoint with optimistic-concurrency token
  revalidation -- eliminates the old opaque "calculate and apply" action and the unsafe
  "maintenance + active booking -> auto rented" shortcut. Frontend
  DataQualityIssueDetail.tsx now shows a review/decide/confirm panel with localized
  why/evidence/consequence text in nl-BE/en-GB/fr-BE, with an exact "Change status to
  <status>" confirm action per the brief.
- Fix MO-016 issue-order dependency: resolving the booking-overlap issue before vs.
  after the status-conflict issue now converges on the same final vehicle status,
  proven by test_mo_016_status_conflict_recommendation_is_order_independent.
- Make "Fleet Ops" a non-localizable brand constant (frontend/src/product.ts,
  backend PRODUCT_NAME) via {{productName}} interpolation everywhere the brand name
  appeared in locale prose; add a permanent test guarding against a translation file
  ever defining the brand name or an "appName" key again.
- Convert dynamic backend prose to stable message codes + params: return status
  reasons, audit field/actor-type labels, automation last_error, and search
  section/vehicle/booking/issue results all now carry codes the frontend localizes,
  with raw technical text demoted to a "Technical details" disclosure.
- docs/fleet-ops-correction/: gap audit, i18n inventory, and the vehicle-status
  decision table documenting the evaluator's rules and safe-status principles.

148 backend tests + Ruff + mypy green; Alembic migration verified upgrade/downgrade;
frontend tsc/build and the i18n-coverage Playwright suite green.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

frontend/src/i18n/locales/en-GB/quality.json

@@ -180,13 +180,48 @@
       "heading": "Resolve the status conflict",
       "description": "One authoritative rule recommends a corrected operational status for this vehicle.",
       "currentStatus": "Current status",
-      "calculateAndApply": "Calculate and apply recommended status",
-      "confirmTitle": "Confirm status change",
-      "confirmBody": "Apply the authoritative recommended status for this vehicle?",
+      "reviewRecommendation": "Review recommendation",
+      "loadingRecommendation": "Loading recommendation…",
+      "recommendationFailed": "Could not load a recommendation.",
+      "recommendedStatus": "Recommended status",
+      "whyHeading": "Why",
+      "evidenceHeading": "Facts",
+      "consequenceHeading": "Consequence",
+      "consequence": {
+        "statusWillChange": "The vehicle status will change to {{status}}.",
+        "issueWillBeRechecked": "This quality issue will be re-checked.",
+        "changeWillBeAudited": "The change will be recorded in the audit trail.",
+        "bookingsNotDeleted": "The bookings themselves are not deleted."
+      },
+      "changeStatusTo": "Change status to {{status}}",
       "applying": "Applying…",
-      "confirmYes": "Yes, apply",
       "applied": "Applied {{status}} — {{reason}}",
-      "applyFailed": "Could not apply a recommended status."
+      "applyFailed": "Could not apply a recommended status.",
+      "staleRecommendation": "The situation has changed since this recommendation was shown. Review it again before applying.",
+      "reviewAgain": "Review recommendation again",
+      "manualReview": {
+        "heading": "Manual review required",
+        "body": "The facts for this vehicle contradict each other. An Operations Manager needs to review this in person rather than apply an automatic status change.",
+        "hint": "Use 'Defer' or 'Reject' below, or investigate the vehicle and the related bookings manually."
+      },
+      "noConflict": {
+        "heading": "No change needed",
+        "body": "This vehicle's current status already matches the facts."
+      },
+      "evidence": {
+        "activeBookings": "Active booking(s): {{refs}}",
+        "overlappingBookings": "Overlapping bookings: {{pairs}}",
+        "serviceThresholdReached": "Odometer reading ({{odometer}} km) has reached the service threshold ({{threshold}} km).",
+        "openOverlapIssue": "Open booking-overlap issue: {{ref}}"
+      },
+      "reasonCodes": {
+        "vehicle.active_rental": "This vehicle has an active rental but is not recorded as rented. The status is corrected to reflect the actual situation.",
+        "vehicle.service_threshold_reached": "This vehicle has reached its service threshold. It is set to maintenance so it is not deployed before servicing takes place.",
+        "vehicle.booking_conflict": "This vehicle has two overlapping bookings. Blocking it prevents it from being considered available again before the booking conflict is resolved.",
+        "vehicle.rental_ended": "The rental for this vehicle has ended and there is no active booking left. It is set back to available.",
+        "vehicle.manual_review_required": "The facts for this vehicle contradict each other (for example, an active booking while the vehicle is in maintenance, or a service threshold reached alongside an active rental). This requires a human review rather than an automatic status change.",
+        "vehicle.no_conflict": "This vehicle's current status already matches the facts. No change is needed."
+      }
     }
   }
 }