Mark protocol versions as generated

[kvz]

Experimental Status

Experimental work: this PR is part of an exploratory contract/generated docs and SDK effort, and is intentionally kept as a Draft while the approach is validated.

Why

This is the first tiny generated island for the API2-owned TUS protocol SDK generator. It lets the API2 generator rewrite and byte-for-byte compare the protocol version constants before expanding into default options and upload behavior.

What

• Mark protocol version constants in lib/options.ts with generated-region markers.
• Keep the generated protocol-version output byte-for-byte identical to the existing constants, aside from markers and the ownership notice.
• Add a generated protocol contract fixture derived from API2 TUS operation contracts, wire version metadata, and client feature metadata.
• Add a real Upload lifecycle test that consumes the generated fixture to assert the generated createTusUpload and patchTusUpload steps against tus-js-client behavior.

Verification

• npm run build-transpile
• npm run test-node
• From API2: api2/bin/cli.ts contracts tus-sdks --platform typescript --sdk-root ../tus-js-client --rewrite-sdk --compare-existing --no-motd

Companion PRs (tus org only)

• tus-go-client: Add generated TUS protocol canary tus-go-client#6
• tus-py-client: Add generated TUS protocol canary tus-py-client#114
• tus-java-client: Add generated TUS protocol contract canary tus-java-client#149
• tus-android-client: Add generated TUS protocol contract canary tus-android-client#167