feat: OpenWhispr-inspired transcription polish pass

Major quality pass on top of Phase 2. Five substantive changes plus
cross-cutting touches across audio, hotkey, transcription, and Tauri
command layers.

  Transcription quality

  - Long-audio chunking in commands/transcription.rs: Parakeet and large
    file transcription now chunk-and-recompose with overlap trimming, so
    the live-path chunking advantage extends to file-based workflows.
  - Stateful live speech gate in commands/live.rs on top of the earlier
    duplicate-boundary filtering — distinguishes start-of-speech from
    mid-speech and holds state across chunks.

  Auto-learning corrections

  - New crates/ai-formatting/src/correction_learning.rs: extracts user
    text corrections from viewer edits and proposes additions to the
    active profile's vocabulary.
  - src-tauri/src/commands/profiles.rs bridge for frontend-driven
    confirmation of learned terms.
  - src/routes/viewer/+page.svelte hooks the learning path into the
    segment-edit flow so corrections feed profile_terms without a
    separate 'train this profile' UX.

  Transcript profile provenance

  - Migration v8 (crates/storage/src/migrations.rs) adds profile_id to
    transcripts, defaulting to DEFAULT_PROFILE_ID so existing rows stay
    valid.
  - crates/storage/src/database.rs: TranscriptRow + CRUD carry profile_id.
  - src-tauri/src/commands/transcripts.rs: add_transcript accepts and
    persists profile_id.
  - DictationPage.svelte + FilesPage.svelte send activeProfileId on
    capture so learned corrections are attributed to the right profile.

  Cleanup prompt contract

  - crates/ai-formatting/src/llm_client.rs hardened: the CLEANUP_PROMPT
    now specifies concrete do/do-not rules, ready for a real model-backed
    cleanup pass. The llm_client is still a stub — kon-llm remains unwired
    — but the prompt shape is final.

  Cross-cutting polish

  - Minor touches in audio (capture/decode/resample), hotkey (lib/linux/stub),
    core, transcription (concurrency/model_manager/local_engine/whisper_rs),
    and the rest of src-tauri/src/commands/*: error-path tightening, log
    clarity, TS-migration follow-ups (@ts-nocheck additions for incremental
    typing).

Verified locally: npm run check, cargo test -p kon-ai-formatting,
cargo test -p kon-storage, cargo test -p kon --lib commands::live::tests,
cargo check — all green.

Scope boundary: kon-llm crate is still a stub; task extraction remains
rule-based. Bundled local-LLM runtime is the next clean step and is not
in this commit.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src-tauri/src/commands/transcripts.rs

@@ -17,8 +17,8 @@ use kon_storage::{
     count_transcripts, delete_transcript as db_delete_transcript,
     get_transcript as db_get_transcript, insert_transcript as db_insert_transcript,
     list_transcripts_paged, search_transcripts as db_search_transcripts,
-    update_transcript as db_update_transcript,
-    update_transcript_meta as db_update_transcript_meta, InsertTranscriptParams, TranscriptRow,
+    update_transcript as db_update_transcript, update_transcript_meta as db_update_transcript_meta,
+    InsertTranscriptParams, TranscriptRow,
 };
 
 use crate::AppState;
@@ -36,6 +36,7 @@ pub struct TranscriptDto {
     pub id: String,
     pub text: String,
     pub source: String,
+    pub profile_id: String,
     pub title: Option<String>,
     pub audio_path: Option<String>,
     pub duration: f64,
@@ -55,6 +56,7 @@ impl From<TranscriptRow> for TranscriptDto {
             id: r.id,
             text: r.text,
             source: r.source,
+            profile_id: r.profile_id,
             title: r.title,
             audio_path: r.audio_path,
             duration: r.duration,
@@ -76,6 +78,7 @@ pub struct CreateTranscriptRequest {
     pub id: String,
     pub text: String,
     pub source: String,
+    pub profile_id: Option<String>,
     pub title: Option<String>,
     pub audio_path: Option<String>,
     pub duration: f64,
@@ -102,6 +105,10 @@ pub async fn add_transcript(
         id: &transcript.id,
         text: &transcript.text,
         source: &transcript.source,
+        profile_id: transcript
+            .profile_id
+            .as_deref()
+            .unwrap_or(kon_storage::DEFAULT_PROFILE_ID),
         title: transcript.title.as_deref(),
         audio_path: transcript.audio_path.as_deref(),
         duration: transcript.duration,
@@ -137,10 +144,10 @@ pub async fn list_transcripts(
 
 /// Total count of transcripts (for "showing X of N" UI).
 #[tauri::command]
-pub async fn count_transcripts_command(
-    state: tauri::State<'_, AppState>,
-) -> Result<i64, String> {
-    count_transcripts(&state.db).await.map_err(|e| e.to_string())
+pub async fn count_transcripts_command(state: tauri::State<'_, AppState>) -> Result<i64, String> {
+    count_transcripts(&state.db)
+        .await
+        .map_err(|e| e.to_string())
 }
 
 #[tauri::command]
@@ -235,4 +242,3 @@ pub async fn update_transcript_meta_cmd(
     .map_err(|e| e.to_string())?;
     Ok(TranscriptDto::from(row))
 }
-