feat(voice): per-account choice between Whisper and the browser; STT_ALLOW_BROWSER

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

frontend/package-lock.json

@@ -1,12 +1,12 @@
 {
   "name": "mindsift-frontend",
-  "version": "0.41.0",
+  "version": "0.42.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "mindsift-frontend",
-      "version": "0.41.0",
+      "version": "0.42.0",
       "license": "Unlicense",
       "dependencies": {
         "@fontsource-variable/inter": "5.3.0",