Rewrite the CLI in Rust with the shared youtubei crate and native FFmpeg

[meoyawn]

Rewrite the CLI in Rust/Cargo while retaining browser authorization, shows/artwork, episodes, resumable uploads, membership, and RSS/YouTube imports. Oasmith generates the public API client and CLIConfig; production defaults are compiled into the binary, and E2Es use validated YAML overrides.

YouTube extraction uses the shared listenbox/youtubei crate pinned to a394160a92d3809bde4d4376d480373bc44ae82e. Rust owns playlist traversal, format selection, HTTP transport and cancellation. The crate downloads the published YouTube.js 18.1.0 CF-worker bundle from its npm archive, verifies both SHA-256 values, and embeds it through QuickJS. Generated JavaScript stays in Cargo's ignored output directory.

The CLI repository has no TypeScript sources, JavaScript package manifests/lockfiles, Nub/Bun dependencies, or bundling tasks. Python's standard library prepares checksum-verified FFmpeg 9.0.2; ffmpeg-the-third statically links its libraries. Building or running the CLI requires no JavaScript toolchain or external FFmpeg/FFprobe executable.

Benchmark rerun on 2026-09-24: Go 3d0f569 versus Rust 637e7c2, including the shared youtubei crate and published YouTube.js 18.1.0 CF-worker bundle.

Metric	Go	Rust	Rust vs. Go
Wall time, including startup	350 ms	484 ms	+38.2%
CPU time (user + system)	200 ms	313 ms	+56.5%
CPU utilization	56.3%	65.6%	+9.2 pp
Peak RAM (RSS)	30.1 MiB	34.0 MiB	+12.8%
Binary size	21.6 MiB	19.9 MiB	-7.8%

Each runtime figure is the median of 20 complete imports after four warmups per build, with balanced Go/Rust/Rust/Go order. Both are stripped release builds with static FFmpeg 9.0.2, on the same eight-vCPU Linux x86-64 host. The local fixture exercises 1080p AVC + Opus download, AAC transcoding, MP4/HLS packaging, upload and successful publication; all 48 imports passed publication and Opus-download checks. Wall time includes startup. CPU and peak RSS cover only the CLI process, excluding backend services; 100% CPU utilization means one occupied core. Deltas use unrounded medians; pp means percentage points. This short local fixture does not measure live YouTube latency, signature challenges or long-video memory use.

Methodology and reproduction · Raw samples and binary hashes · Host and build details.

Validation:

• cli:check: formatting, Clippy, unit tests, debug smoke test, release build and package passed.
• API integration: 64 CLI tests/subtests passed, including playlist imports, AVC/Opus conversion, quota rejection, partial-upload cleanup, interruption after admission, and lost completion acknowledgements. All six YouTube scenarios finished in under ten seconds.
• Fresh standalone checkout with no native/Cargo outputs: cli:smoke and cli:test passed with Node, Nub, Bun and esbuild blocked on PATH.
• Shared crate: 15 runtime tests and Clippy passed; Git and Cargo package contents exclude the bundle. Workflow actionlint passed.

Full workspace verification was not rerun; the previously reported RSS import deadlock is outside this change. Tests use local fixtures, without live YouTube or cross-platform release validation.

Related: workspace integration #88, Oasmith Rust generation #14, and Mazit shared dependency #2. The Go baseline from #7 is already merged.