Introduce persistent generationStatus to work summaries (puzzle & match3d) and propagate generation recovery rules across docs and frontend/backends so "generating" is restored from server-side work summary rather than ephemeral front-end notices. Update API server image/asset handling (improve match3d material sheet green/alpha decontamination and promote generatedItemAssets background fields) and add runtime improvements: alpha-based hotspot hit-testing, tray insertion/three-match animation behavior, and session re-read on client-side VectorEngine timeouts/lock-screen interruptions. Many docs, tests and related frontend modules updated/added to reflect these contract and behavior changes.
Backend: stop treating background music as a required draft asset and remove auto-submit/plan for background music; load persisted generated UI/assets into Match3D agent session responses (added helpers to resolve profile id and fetch existing generated assets). Frontend: make Match3D result preview reuse runtime UI styles, unify runtime settings entry, update PuzzleRuntime to apply immediate pointermove transforms (disable drag transition), use SVG clipPath for merged piece rounding, ensure PuzzleRuntimeShell supplies platform theme classes, and adjust related tests. Docs & logs: update decision log, pitfalls and product docs to reflect these changes.
