feat(voice): adapt voice entry to the stacked-jobs prosthesis model

Authored by the /orchestrate builder agent, committed unrepaired so the
fixes that follow are reviewable against it.

Backend: replaces the flat prosthesisDefaultType/prosthesisOverrides wire
shape with a prosthesis: ProsthesisAssignment[] list whose targets can be a
tooth or a jaw; adds resolveAssignmentTarget / classifyTypeCode /
resolveProsthesisAssignment for leaf-vs-category classification, region
validity with mixed-region deferral, and assignmentIndex on unresolved
items; adds PROSTHESIS_CATEGORY and PROSTHESIS_SUBCATEGORY to
CatalogEntityKind with a migration and seeded fa/en/nl translations; and
rewrites the extraction prompt to render the catalog as a tree.

Frontend: merged "teeth and prosthesis" row, stack preview through the
existing applyLeafToJobs, three chip-fold paths, rewritten applyVoiceResult
and voiceForEditor, and the two carried-forward recording fixes — the
container fallback that refused Safari and the render gate that never
checked isMediaRecorderSupported().

Adds Vitest for the frontend's pure helpers, and updates CLAUDE.md.

Gate was green: backend 16 suites / 209 tests, nest build, prisma validate;
frontend 37 Vitest tests, tsc --noEmit, next build.

KNOWN DEFECTS, fixed in the commits that follow:
- VoiceReviewSheet.tsx:169 — a picked tooth chip is dropped on Apply
- VoiceReviewSheet.tsx:213 / TreatmentWorkspace.tsx:2215 — decision 41's
  type-row lock is missing, so unticking it saves prosthesis lab rows on a
  non-prosthesis detail

Reviewed on the correctness lens only; regression-risk never ran. The
migration was validated but never applied.

Spec: docs/specs/voice-treatment-entry/spec.md
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

frontend/messages/en.json

@@ -926,20 +926,25 @@
     "voiceProcessing": "Reading the recording…",
     "voiceReviewTitle": "Check what was understood",
     "voiceNothingExtracted": "Nothing usable was picked up from that recording.",
-    "voiceProsthesisIncomplete": "No prosthesis type for {teeth} — the case cannot be sent until every tooth has one.",
     "voiceLabInexact": "The spoken name only partly matched this lab. Confirm before sending.",
     "voiceNotUnderstood": "Not understood",
     "voicePickTooth": "Which tooth?",
+    "voicePickJaw": "Which jaw?",
+    "voiceTeethAndProsthesis": "Teeth and prosthesis",
+    "voiceNoProsthesisHeard": "no prosthesis heard",
+    "voiceStackRefused": "not added — cannot be combined",
     "voiceDiscard": "Discard",
     "voiceApply": "{count, plural, one {Apply # field} other {Apply # fields}}",
     "voiceUnresolved": {
       "not_permanent_tooth": "not a permanent tooth",
       "position_out_of_range": "not a valid tooth position",
       "tooth_missing_quadrant": "not a whole tooth number — say e.g. “twenty-six”",
+      "prosthesis_type_ambiguous": "a general term, not a specific material — pick one below",
+      "arch_not_spoken": "which jaw was this for? — pick below",
+      "code_not_valid_for_target": "does not fit that tooth or jaw",
       "malformed": "could not be read",
       "span_not_same_arch": "a bridge cannot span both jaws",
       "unknown_catalog_code": "not in this clinic’s list",
-      "tooth_not_selected": "that tooth is not part of this detail",
       "invalid_date": "not a usable date"
     },
     "voiceFailed": "Voice entry failed. Please try again."