Write contributor-facing docs for the semantic services used by the copilot workflow.\n\nAcceptance criteria:\n- Explain what project/video context is indexed.\n- List extension points and expected inputs/outputs.\n- Include privacy notes for local media and project data.
Write contributor-facing docs for the semantic services used by the copilot workflow.\n\nAcceptance criteria:\n- Explain what project/video context is indexed.\n- List extension points and expected inputs/outputs.\n- Include privacy notes for local media and project data.