Step 2 of video assembly. Create a CueFrame project for any video style (1A demo, 1B PIP-avatar, 1C conceptual, 1D launch). Returns a project_id used by put_composition + render. Params: name (required), format {aspectRatio 16:9|9:16|1:1|4:5, fps 24|30|60, resolution hd|fhd|4k}, optional width/height/brandKitId.