MeTube project notes

Versioning rule

The version number checked into git (recorded in DEPLOY.md) is the current online version — the version of the latest published Docker image.
When any changes are made, the new Docker image version must bump the minor number of the latest git version (e.g. latest is 1.9 → new image is 1.10).
The version is injected into the image at build time via --build-arg VERSION=<version> (exposed as METUBE_VERSION and served by the /version endpoint).
Whenever a new image is built and pushed, update the build/push commands in DEPLOY.md in the same commit so the checked-in version always matches the published image.
Use ./publish.sh to publish: it bumps the minor version from DEPLOY.md, updates DEPLOY.md, builds and pushes the image. Pass an explicit version (./publish.sh 2.0) to override. Do not run it unless the user asked to publish.

Angular app in ui/. Build with cd ui && npm run build. The Docker image builds the UI itself (see Dockerfile), so no need to commit ui/dist.

LIBRARY_DIR (empty = feature off) points to a separate media library directory, mounted as its own volume. See LIBRARY_ORGANIZE_DESIGN.md for the full design.
Library state is read from disk on demand — no DB/index. /library/folders is cached ~60s in memory; organize/delete invalidate it.
Organizing a completed download moves its file into the library and removes the done entry (a cleared socket event updates the UI).
At organize time a hidden sidecar .<filename>.metube.json is written next to the video with source metadata (url, title, uploader, website, downloaded_at) — see library_meta_path() in app/ytdl.py. /library/files attaches it as meta; library delete removes it. Files organized before this existed have no sidecar.