Add generationStatus and match3d/runtime fixes

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.

src/services/miniGameDraftGenerationProgress.ts

@@ -59,6 +59,7 @@ export type MiniGameDraftGenerationState = {
   kind: MiniGameDraftGenerationKind;
   phase: MiniGameDraftGenerationPhase;
   startedAtMs: number;
+  finishedAtMs?: number;
   completedAssetCount: number;
   totalAssetCount: number;
   error: string | null;
@@ -445,7 +446,11 @@ export function buildMiniGameDraftGenerationProgress(
     return null;
   }
 
-  const elapsedMs = Math.max(0, nowMs - state.startedAtMs);
+  const effectiveNowMs =
+    typeof state.finishedAtMs === 'number' && Number.isFinite(state.finishedAtMs)
+      ? state.finishedAtMs
+      : nowMs;
+  const elapsedMs = Math.max(0, effectiveNowMs - state.startedAtMs);
   const puzzleTimeline =
     state.kind === 'puzzle' &&
     state.phase !== 'failed' &&