feat: persist global track visibility status and metronome status

src/core/project-upgrader/KGProjectUpgrader.ts

@@ -14,6 +14,7 @@ import { upgradeToV12 } from './upgradeToV12';
 import { upgradeToV13 } from './upgradeToV13';
 import { upgradeToV14 } from './upgradeToV14';
 import { upgradeToV15 } from './upgradeToV15';
+import { upgradeToV16 } from './upgradeToV16';
 
 /**
  * Upgrade the given project to the latest structure version, one version at a time.
@@ -93,6 +94,10 @@ export function upgradeProjectToLatest(project: KGProject): KGProject {
         workingProject = upgradeToV15(workingProject);
         break;
       }
+      case 16: {
+        workingProject = upgradeToV16(workingProject);
+        break;
+      }
       default: {
         // If an upgrader is missing, throw to prevent loading incompatible structures
         throw new Error(`No upgrader found for project structure version ${nextVersion}`);

src/core/project-upgrader/upgradeToV16.test.ts

@@ -0,0 +1,26 @@
+import { describe, expect, it } from 'vitest';
+import { KGProject } from '../KGProject';
+import { upgradeProjectToLatest } from './KGProjectUpgrader';
+import { upgradeToV16 } from './upgradeToV16';
+
+describe('upgradeToV16', () => {
+  it('defaults persisted UI/audio toggles to false for legacy projects', () => {
+    const project = new KGProject('Legacy', 32, 0, 125, undefined, undefined, undefined, undefined, [0, 0], 1, [], 15, 1, []);
+
+    upgradeToV16(project);
+
+    expect(project.getProjectStructureVersion()).toBe(16);
+    expect(project.getShowGlobalTracks()).toBe(false);
+    expect(project.getIsMetronomeEnabled()).toBe(false);
+  });
+
+  it('preserves existing persisted toggle values through the main upgrader path', () => {
+    const project = new KGProject('Legacy', 32, 0, 125, undefined, undefined, undefined, undefined, [0, 0], 1, [], 15, 1, [], true, true);
+
+    const upgraded = upgradeProjectToLatest(project);
+
+    expect(upgraded.getProjectStructureVersion()).toBe(KGProject.CURRENT_PROJECT_STRUCTURE_VERSION);
+    expect(upgraded.getShowGlobalTracks()).toBe(true);
+    expect(upgraded.getIsMetronomeEnabled()).toBe(true);
+  });
+});

src/core/project-upgrader/upgradeToV16.ts

@@ -0,0 +1,17 @@
+import { KGProject } from '../KGProject';
+
+export function upgradeToV16(project: KGProject): KGProject {
+  try {
+    if (typeof project.getShowGlobalTracks() !== 'boolean') {
+      project.setShowGlobalTracks(false);
+    }
+
+    if (typeof project.getIsMetronomeEnabled() !== 'boolean') {
+      project.setIsMetronomeEnabled(false);
+    }
+  } finally {
+    project.setProjectStructureVersion(16);
+  }
+
+  return project;
+}