feat(exam,result): quick status action, per-row publish

Two UX gaps found in testing:

- Exams list: changing status (e.g. PENDING -> ACTIVE) required opening the
  full Edit modal for a one-field change. Added a status menu (teal toggle
  icon) directly in the row actions, calling PUT /exams/:id with just
  {status} — the backend DTO was already PartialType, nothing to change
  there.
- Exam Results: publishing required first picking the exam in a page-level
  filter to un-grey the header Publish button — not discoverable, and an
  extra step disconnected from the row you actually care about. Added a
  Publish action directly on any APPROVED result's row, confirm-gated since
  it publishes every approved result for that exam (not just the one row)
  and notifies every candidate. The header filter+button still works too,
  for publishing a batch at once.

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

apps/backoffice/src/app/i18n/locales/am.ts

@@ -660,6 +660,8 @@ export const am: Translations = {
       returned: "ውጤት ወደ ፈታኙ ተመልሷል",
       publishedCount: "{{published}} ውጤቶች ወጥተዋል፤ {{skipped}} ተዘለዋል።",
       publishNeedsExam: "ውጤቶችን ለማውጣት መጀመሪያ በፈተና ያጣሩ።",
+      publishConfirmText:
+        "ይህ ለ{{exam}} የጸደቁትን ሁሉንም ውጤቶች ያወጣል — ይህን ብቻ አይደለም — እና እያንዳንዱን ተፈታኝ ያሳውቃል። ይቀጥል?",
       lockedAfterApproval: "ይህ ውጤት ጸድቋል፤ ማስተካከል አይቻልም። መጀመሪያ ወደ ፈታኙ ይመልሱት።",
       originalScore: "የፈታኙ ጠቅላላ",
       derivedStatus: "ውጤት (ከማለፊያ ነጥብ የተገኘ)",

apps/backoffice/src/app/i18n/locales/en.ts

@@ -660,6 +660,8 @@ export const en = {
       returned: 'Result returned to the examiner',
       publishedCount: 'Published {{published}} result(s); {{skipped}} skipped.',
       publishNeedsExam: 'Filter by an exam first to publish its results.',
+      publishConfirmText:
+        'This publishes every approved result for {{exam}} — not just this one — and notifies each candidate. Continue?',
       lockedAfterApproval:
         'This result is approved and can no longer be edited. Return it to the examiner first.',
       originalScore: 'Examiner total',