Motion Mix Live Director Mac4 Camera 7/8/9 Handoff

This handoff is for the agent integrating the three new Mac4 camera lanes into Motion Mix Live Director and the Motion Mix Wall. No Live Director application code was changed in this pass. | Camera | Device | ID | Host | Port | Token | Status | | --- | --- | --- | --- | --- | --- | --- | | 7 | Insta360 X4 | `mac4-camera7-insta360` | `[ip]` | `8087` | `mac4camera7` | registered lane service alive; selects `Insta360 X4` | | 8 | Orbbec Femto Mega RGB Camera | `mac4-camera8-femto-mega` | `[ip]` | `8088` | `mac4camera8` | registered lane service alive; selects `Orbbec Femto Mega RGB Camera` | | 9 | Orbbec Femto Bolt RGB Camera | `mac4-camera9-femto-bolt` | `[ip]` | `8089` | `mac4camera9` | registered lane service alive; selects `Orbbec Femto Bolt RGB Camera` | Each lane probes AVFoundation with ffmpeg, selects the camera by name/regex, and refuses unwanted devices through exclude patterns. This is important because AVFoundation indices changed while testing; the integration should not depend on index `0`, `1`, or `2`. The `/status` endpoints are confirmed good and currently identify all three physical cameras correctly. Frame capture still needs one final operator-side fix before treating the feeds as video-ready in production. During this pass, ffmpeg could enumerate the cameras and report supported formats, but `/snapshot` and `/mjpeg` timed out while trying to pull frames. The likely causes are: