feat: wire voice entry into the treatment workspace

Makes the feature reachable end to end: availability is fetched alongside the
catalogs, the capture hook drives the segmented control, and confirming the
review sheet appends a new detail.

Confirm always appends — it never edits an existing detail and never calls
onAddDetail. Ticked rows land on top of the seeded defaults, so unticking the
type row leaves the appointment-purpose default rather than a blank. Lab-side
rows ride on a lab case draft keyed by the detail's *client* id, so a brand-new
unsaved detail can carry a lab, due date and per-tooth prosthesis map.

Availability comes from the API rather than a NEXT_PUBLIC_* var, since those are
baked in at build time; a failure fetching it degrades to no microphone rather
than taking the treatment tab down.

From review of this commit:

- Unticking "teeth" while leaving "prosthesis" ticked attached prosthesis rows
  for teeth the detail does not contain. Nothing downstream filters them —
  assertCompleteToothProsthesisMap only checks detail-teeth ⊆ map, never the
  reverse — so they would have reached task generation as lab work for teeth
  nobody is treating. The map is now filtered to the detail's own teeth.
- The microphone was gated on the URL locale while the server resolved
  everything from req.user.language. Those diverge (a bookmarked /fa/ URL, a
  language toggle whose save failed), which would transcribe Persian with an
  English hint and anchor "next Thursday" to a Monday week instead of a Saturday
  one — or 403 from a visibly-enabled button. The client now sends the locale the
  microphone was offered in, so the gate and the request agree by construction.

Also fixed from the previous review: a civil YYYY-MM-DD date rendered a day
early west of Greenwich (parsed as UTC midnight); the missing-teeth list
hardcoded the Arabic comma for all locales; and voiceApply had no ICU plural, so
the common single-field case read "Apply 1 fields".

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

backend/src/modules/voice/extraction.resolver.ts

@@ -287,10 +287,10 @@ export function resolveVoiceIntent(
   // reported: a hallucinated lab must not look identical to "no lab was spoken".
   const labId = resolveCatalogCode(intent?.labId, ctx.linkedLabIds);
   if (intent?.labId != null && !labId) {
-    unresolved.push({
-      spoken: String(intent.labId),
-      reason: 'unknown_catalog_code',
-    });
+    // `spoken` means "what the clinician said". A rejected lab id is an opaque
+    // identifier the model invented, so quoting it back would put a raw UUID in front
+    // of the user; the reason alone carries the meaning.
+    unresolved.push({ spoken: '', reason: 'unknown_catalog_code' });
   }
 
   return {