v7: standalone Sing Detect app — full Tauri project tree

Promotes the v6 detection slice into a complete, buildable Tauri 2 app and
renames Stream Studio → Sing Detect (detection-only; video-concat split to its
own project). Proper src/ + src-tauri/ layout, Python sidecar under sidecar/,
app icons, package/Cargo manifests, and dev/build/pack scripts.

Pipeline unchanged in spirit: Rust drives ffmpeg to a 16 kHz mono WAV, the
Python sidecar (inaSpeechSegmenter) emits line-JSON segments, and Rust writes
EDL / markers CSV / CSV / JSON exports. Long ops run on spawn_blocking; cancel
kills the whole py -3.10 process tree.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

sidecar/setup_sidecar.bat

@@ -0,0 +1,25 @@
+@echo off
+REM Install the singing-detection ML dependencies into Python 3.10.
+REM TensorFlow does not support Python 3.12+, so we pin 3.10 via the py launcher.
+
+py -3.10 --version >nul 2>&1
+if errorlevel 1 (
+  echo Python 3.10 not found via the "py" launcher.
+  echo Install Python 3.10 from https://www.python.org/downloads/release/python-31011/
+  echo Then re-run this script.
+  pause
+  exit /b 1
+)
+
+echo Installing inaSpeechSegmenter + TensorFlow into Python 3.10...
+py -3.10 -m pip install --upgrade pip
+py -3.10 -m pip install -r "%~dp0requirements.txt"
+
+REM Re-pin NumPy last: TensorFlow can drag NumPy 2.x back in, which crashes TF
+REM with "_pywrap_bfloat16.TF_bfloat16_type() () -> handle".
+py -3.10 -m pip install "numpy<2"
+
+echo.
+echo Verifying...
+py -3.10 -c "from inaSpeechSegmenter import Segmenter; print('inaSpeechSegmenter OK')"
+pause