Hardware-gated smoke test and release hardening for sidecar

[rupertgermann]

Parent

• PRD: Real freemocap sidecar service #68

What to build

Add the final verification and release-hardening layer for the real sidecar. The project should have a documented hardware-gated smoke test for a real FreeMoCap camera rig, plus automated package/release checks that prevent regressions in installability, CLI startup, sidecar contract compatibility, and app capture compatibility.

Acceptance criteria

• A hardware-gated smoke test procedure records a real camera-rig session through Rowing Tracker and verifies replay/analysis output.
• The hardware smoke path is documented as manual or opt-in and does not block normal CI when hardware is unavailable.
• Automated release checks verify the supported package install path and rowing-tracker-sidecar console script startup.
• Automated checks verify the sidecar contract using the deterministic source against the Rowing Tracker app-side client.
• Version/schema compatibility is documented so the app can reject incompatible sidecar builds predictably.
• Release notes or setup docs explain whether the package is repo-local only or published, and how users should install the correct build.
• Privacy expectations are verified or documented: local-only binding by default, no cloud calls from the sidecar, and no raw 3D frames sent to cloud AI.

Blocked by

• Start and stop real sidecar capture from Rowing Tracker #72
• Sidecar diagnostics, docs, and local install flow #73