Decouple transcripts from note text; end-to-end watch transfer acks

Schema v3: transcription attempts accumulate on AudioInfo (text, locale,
confidence, forced flag) — latest attempt is displayed, payload.text is
purely user writing, v2 notes migrate at read time. Editor shows the
transcript in its own live-updating section with insert-into-note; search
matches transcripts weighted by confidence. Watch recordings are now
deleted only on the phone's durable-ingest ack (transferUserInfo), closing
every phone-side loss window; failed sidecar writes unstage instead of
orphaning, and unreadable inbox recordings are surfaced in logs.

Claude-Session: https://claude.ai/code/session_014esDWi42URLEC6Cj17hGQ3

README.md

@@ -11,11 +11,12 @@ the top of the list.
 
 - **Quick text notes** — jot something down in two taps; first line doubles as the title
 - **Voice notes** — record a memo (iPhone, Mac, or Apple Watch); the audio is kept and transcribed on-device afterwards, with a per-note "re-transcribe in another language" override and a settings screen to enable transcription languages
-- **Apple Watch capture** — a watch-face complication opens a one-button recorder; the recording transfers to your iPhone over WatchConnectivity, which ingests and transcribes it (no iCloud on the watch)
+- **Transcripts kept separate from your text** — every transcription attempt is preserved on the note (latest shown, with language and confidence); your own typing is never mixed with or overwritten by machine output, and a transcript can be inserted into the note body on demand
+- **Apple Watch capture** — a watch-face complication opens a one-button recorder; the recording transfers to your iPhone over WatchConnectivity, which ingests and transcribes it (no iCloud on the watch); the watch keeps its copy until the iPhone acknowledges durable ingest, so a failed handoff never loses audio
 - **Automatic context capture** — location, place name (reverse-geocoded), time zone, and device are stamped onto every note, best-effort and privacy-friendly (all data stays in your iCloud)
 - **"Right here, right now" recall** — a ranked shelf of notes whose capture context matches your current place and time, above the regular newest-first list
 - **Tags** — manual organization alongside the automatic context; browse notes by tag
-- **Search** — full-text over note text, tags, and captured place names
+- **Search** — full-text over note text, voice transcripts (weighted by transcription confidence), tags, and captured place names
 - **iCloud sync** — notes live as JSON files in your iCloud Drive (visible in Files.app) and sync across iPhone and Mac; the local database is just a rebuildable cache
 - **iOS + macOS + watchOS** — same app and data across iPhone and Mac, with an Apple Watch companion for voice capture
 - **Backups** — one-tap local backup and restore of all notes (IndieBackup); backup files can be shared and imported across devices