fix: use Float progress for CircularProgressIndicator (Material3 1.1.x compat)

feat: add LessonPracticeScreen with timer, encouragement, and lively UI

feat: add LessonDetailScreen with clickable lesson cards and navigation

fix: replace embedded ASCII quotes with corner brackets to fix Kotlin compilation

feat: 扩充课程到30节、每日任务到30天、成就到20个 - 活泼教学设计

Fix: add permissions for GitHub Release creation

Fix: LinearProgressIndicator API and FilterChip @OptIn annotation

Fix: use gradle/actions/setup-gradle to generate wrapper in CI

Add GitHub Actions workflow for APK build

🎤 Initial commit: VocalCoach - 流行演唱声乐教学App