feat: playback bar component, save system improvements, demo and roadmap updates

engine/systems/SaveSystem.ts

@@ -16,15 +16,22 @@ interface UnlockRecord {
   chapterId: string
 }
 
+interface WatchedRecord {
+  sceneId: string
+  timestamp: number
+}
+
 class SaveDB extends Dexie {
   saves!: Table<SaveRecord, number>
   unlocks!: Table<UnlockRecord, string>
+  watched!: Table<WatchedRecord, string>
 
   constructor() {
     super('MovieGameSaves')
-    this.version(3).stores({
+    this.version(4).stores({
       saves: '++id, slot',
       unlocks: 'chapterId',
+      watched: 'sceneId',
     })
   }
 }
@@ -96,4 +103,21 @@ export class SaveSystem {
     const records = await db.unlocks.toArray()
     return records.map((r) => r.chapterId)
   }
+
+  async markWatched(sceneId: string) {
+    const exists = await db.watched.get(sceneId)
+    if (!exists) {
+      await db.watched.put({ sceneId, timestamp: Date.now() })
+    }
+  }
+
+  async isWatched(sceneId: string): Promise<boolean> {
+    const record = await db.watched.get(sceneId)
+    return !!record
+  }
+
+  async getWatchedSceneIds(): Promise<string[]> {
+    const records = await db.watched.toArray()
+    return records.map((r) => r.sceneId)
+  }
 }