Main-screen recordings list, player actions, background recording, exports (1.4.0-alpha)

- Main screen: recordings list at the bottom (newest first); removed the separate
  library screen and the top-right link
- Player: delete/rename/share/export, no autoplay, embedded-marker fallback
- Word-level tap-to-seek from Whisper token timestamps (length fallback)
- Export transcripts as .txt + .srt to Downloads
- RecordingService: microphone foreground service for background recording
- FileProvider for sharing on Android 9 and older
- StreamingResampler extracted to its own class + JUnit regression tests
- Bump to 1.4.0-alpha (versionCode 6)

1 files changed, 11 insertions, 9 deletions

diff --git a/TODO.md b/TODO.md
index c41f23e..1fa9671 100644
--- a/TODO.md
+++ b/TODO.md
@@ -21,15 +21,17 @@
       columns.
 - [x] **WAV markers** — done: the **Mark** button embeds `cue `/`adtl` chunks in
       the WAV and stores a JSON sidecar; the player shows marker chips.
+- [x] **Recordings list on the main screen** — done: the top-right *Recordings*
+      link is replaced by a scrollable list at the bottom of the main screen,
+      newest first. Tapping a row opens the player. The player has a **Delete**
+      button and no longer autoplays.
 
-## Backlog (from earlier discussion)
+## Backlog
 
-- [ ] Export transcripts as `.txt` / `.srt` and/or embed them in WAV metadata
-      (`LIST`/`INFO`, `bext`).
-- [ ] Foreground service so recording continues when the app is in the
+- [x] Export transcripts as `.txt` / `.srt` (saved to Downloads, plus share).
+- [x] Foreground service so recording continues when the app is in the
       background.
-- [ ] Library actions: delete, rename, share, "open with".
-- [ ] Word-level timestamps and tap-to-seek inside a transcript segment.
-- [ ] Read embedded markers back from the WAV when there is no JSON sidecar.
-- [ ] Add a JUnit regression test for `StreamingResampler` (it could throw
-      `IllegalArgumentException: <n> > <n-1>` when the trim overshot the buffer).
+- [x] Library actions: delete, rename, share, "open with".
+- [x] Word-level tap-to-seek inside a transcript segment.
+- [x] Read embedded markers back from the WAV when there is no JSON sidecar.
+- [x] Add a JUnit regression test for `StreamingResampler`.