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>

backend/app/schemas.py

@@ -83,6 +83,8 @@ class ReturnPreviewResult(BaseModel):
     resulting_odometer_km: int
     resulting_vehicle_status: str
     status_reason: str
+    status_reason_code: str
+    status_reason_params: dict[str, str | int] = {}
     would_create_quality_issue: bool
     attention_reasons: list[str]
     next_booking_risk: NextBookingRisk | None
@@ -157,16 +159,41 @@ class ResolveOverlapRequest(BaseModel):
     note: str | None = Field(default=None, max_length=500)
 
 
+class VehicleStatusFactsOut(BaseModel):
+    active_booking_refs: list[str]
+    overlapping_booking_pairs: list[list[str]]
+    service_threshold_reached: bool
+    odometer_km: int
+    next_service_km: int
+    open_booking_overlap_issue_ref: str | None = None
+
+
+class StatusRecommendationOut(BaseModel):
+    current_status: str
+    recommended_status: str | None
+    recommendation_code: str
+    safe_to_apply: bool
+    manual_review_required: bool
+    facts: VehicleStatusFactsOut
+    blocking_reasons: list[str]
+    recommendation_token: str
+
+
+class ApplyRecommendedStatusRequest(BaseModel):
+    recommendation_token: str
+
+
 class ApplyRecommendedStatusResult(BaseModel):
     issue: DataQualityIssueOut
     applied_status: str
-    reason: str
+    reason_code: str
 
 
 class SearchResultItem(BaseModel):
     type: Literal["vehicle", "booking", "data_quality_issue", "section"]
     label: str
-    detail: str
+    detail_code: str
+    detail_params: dict[str, str] = {}
     link: str
 
 
@@ -269,6 +296,7 @@ class AutomationRunOut(BaseModel):
     status: str
     attempts: int
     last_error: str | None
+    last_error_code: str | None
     occurred_at: datetime