fix: direct venv python in entrypoint, fix INSIGHTFACE_HOME path, add badges

- entrypoint.sh: replace `uv run` with `/app/.venv/bin/python` to skip
  uv's sync check which was re-downloading ruff and rebuilding the package
  on every container startup
- compose.yml, .env.example: fix INSIGHTFACE_HOME /models → /models/.insightface;
  InsightFace appends models/ to root, so /models produced /models/models/buffalo_l
- README.md: add Immich and Frigate badges from upstream
- CHANGELOG.md, pyproject.toml, uv.lock: bump to 0.2.1

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

entrypoint.sh

@@ -4,13 +4,13 @@ export PYTHONUNBUFFERED=1
 
 # 1. Run the job immediately on startup
 echo "▶ Running on startup..."
-uv run python -m winnow.cli
+/app/.venv/bin/python -m winnow.cli
 
 # 2. If a schedule exists, start the scheduler
 if [ -n "${CRON_SCHEDULE:-}" ]; then
     echo "▶ CRON_SCHEDULE set to: $CRON_SCHEDULE"
     echo "▶ Switching to scheduled mode..."
-    exec uv run python3 /app/scheduler.py
+    exec /app/.venv/bin/python /app/scheduler.py
 else
     echo "▶ No schedule set, exiting."
 fi