Primary router and workflow for AI video generation with Seedance2 / SD2 on StoReel Canvas. Use whenever the user asks to generate, continue, extend, remake, batch, or finish AI videos; create image-to-video or reference-video clips; write SD2 video prompts; bind first frames, character references, product references, or previous video references; poll tasks, write results back to canvas, save local deliverables, or switch StoReel accounts when quota/points are exhausted.