agent: code-atomiser-fix — Tauri commands for trash list + restore

Adds two `#[tauri::command]` wrappers around the soft-delete pair that
landed with migration v16 in commit 15b74db:

  - `list_trashed_transcripts(limit, offset)` mirrors the existing
    `list_transcripts` shape (default 50, clamp 1..=500, offset >= 0)
    so the Trash view can paginate the `deleted_at IS NOT NULL`
    partition with the same UX as the live history list.

  - `restore_transcript(id)` clears `deleted_at`. Idempotent on a live
    row, per the storage-layer contract. Audio at `audio_path` may
    already have been removed by `delete_transcript`'s best-effort
    filesystem cleanup; the text + metadata recovery is what
    restoration actually buys you.

Both are registered in the `tauri::generate_handler!` block in
`src-tauri/src/lib.rs`, alongside the existing transcripts surface.
Mirrors the signature shape of `delete_transcript` — no
`ensure_main_window` because the rest of the transcripts command
surface does not gate on it; introducing that here would be
inconsistent and out of scope for this fix.

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

src-tauri/src/lib.rs

@@ -719,6 +719,8 @@ pub fn run() {
             commands::transcripts::update_transcript,
             commands::transcripts::update_transcript_meta_cmd,
             commands::transcripts::delete_transcript,
+            commands::transcripts::list_trashed_transcripts,
+            commands::transcripts::restore_transcript,
             commands::transcripts::search_transcripts,
             // Diagnostics (panic + error capture, manual report bundle)
             commands::diagnostics::log_frontend_error,