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/pages/Automation.tsx

@@ -118,7 +118,21 @@ export function Automation() {
           <StatusBadge status={r.status} label={t(`ledger.status${r.status.charAt(0).toUpperCase()}${r.status.slice(1)}`)} />
         </td>
         <td data-label={t("ledger.columns.attempts")}>{r.attempts}</td>
-        <td data-label={t("ledger.columns.lastError")}>{r.last_error ?? "—"}</td>
+        <td data-label={t("ledger.columns.lastError")}>
+          {r.last_error_code ? (
+            <>
+              <span>{t(`ledger.errorCodes.${r.last_error_code}`, { defaultValue: r.last_error ?? r.last_error_code })}</span>
+              {r.last_error && (
+                <details className="evidence-disclosure">
+                  <summary>{t("common:actions.technicalDetails")}</summary>
+                  <pre className="evidence-block">{r.last_error}</pre>
+                </details>
+              )}
+            </>
+          ) : (
+            "—"
+          )}
+        </td>
         <td data-label={t("ledger.columns.when")}>
           <time dateTime={r.occurred_at}>{formatDateTime(r.occurred_at)}</time>
         </td>