Add native Android app scaffold (M0): whisper.cpp engine via JNI

- android/: Gradle/Kotlin project (AGP 9.4, Compose, NDK 27.1), monorepo
  subdir as planned; whisper.cpp v1.9.3 vendored via pinned fetch script
- core/whisper: JNI wrapper (beam size, threads, language) + WhisperEngine
  Kotlin API mirroring the desktop engine contract
- app (M0 scope): in-app GGML model download from Hugging Face, engine
  load, WAV picker with resampling, on-device transcription, share sheet
- build validated: assembleDebug OK, libwhisper_jni.so + ggml packaged

README.md

@@ -2,12 +2,13 @@
 
 Record an in-person meeting and transcribe it with [Whisper](https://github.com/SYSTRAN/faster-whisper).
 
-Meetrec captures audio from any PipeWire/ALSA input (microphone, USB conference mic, USB audio interface, or a Pulse/PipeWire sink *monitor*) and produces transcripts in `txt`, `srt`, and `json`. It runs fully locally — no audio ever leaves your machine.
+Meetrec captures audio from any input (microphone, USB conference mic, USB audio interface, or a Pulse/PipeWire sink *monitor*) and produces transcripts in `txt`, `srt`, and `json`. It runs fully locally — no audio ever leaves your machine.
 
-Two interfaces:
+Two desktop interfaces plus an Android app:
 
 - **`meetrec.py`** — CLI: record, optionally show a live rolling transcript, and on `Ctrl+C` run a final higher-quality pass.
 - **`meetrec_gui.py`** — Qt (PySide6) GUI: device/model/language selection, level meter, live transcript, and one-click *Stop & transcribe*.
+- **`android/`** — native Kotlin app with the same on-device functionality, built on whisper.cpp via JNI (see `android/README.md`).
 
 ## Output files
 
@@ -136,6 +137,7 @@ install.sh            install / uninstall into a local prefix
 bin/meetrec           GUI launcher (installed into ~/.local/bin)
 bin/meetrec-cli       CLI launcher (installed into ~/.local/bin)
 share/applications/meetrec.desktop   XDG desktop entry
+android/              native Android app (Kotlin + whisper.cpp JNI)
 ```
 
 ## Privacy