M2: timeline, audio graph, ambient, procedural SFX, effects, player with pause/replay, transcript; voice pacing fixes

master

Commit

Mrituanjay Nath Jha2d ago

Co-Authored-By: Claude Sonnet 5.5 noreply@anthropic.com Entire-Checkpoint: 01M63DGA2VX1NZ8P2SDESHPSAV