feat: add minimal Capacitor test apps for all platforms

- Add Android test app with exact alarm permission testing
- Add iOS test app with rolling window and BGTaskScheduler testing
- Add Electron test app with mock implementations and IPC
- Include automated setup scripts for each platform
- Provide comprehensive testing checklist and troubleshooting guide
- Follow best practices for Capacitor plugin testing

Test apps include:
- Plugin configuration and scheduling validation
- Platform-specific feature testing (Android exact alarms, iOS rolling window)
- Performance monitoring and debug information
- Error handling and edge case testing
- Cross-platform API consistency validation

Setup: Run ./setup-*.sh scripts for automated platform setup
Testing: Each app provides interactive UI for comprehensive plugin validation

Files: 25+ new files across test-apps/ directory

test-apps/android-test/.gitignore

@@ -0,0 +1,105 @@
+# Dependencies
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+
+# Build outputs
+dist/
+build/
+*.tsbuildinfo
+
+# Capacitor
+android/
+ios/
+.capacitor/
+
+# IDE and editor files
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+
+# OS generated files
+.DS_Store
+.DS_Store?
+._*
+.Spotlight-V100
+.Trashes
+ehthumbs.db
+Thumbs.db
+
+# Logs
+logs
+*.log
+
+# Runtime data
+pids
+*.pid
+*.seed
+*.pid.lock
+
+# Coverage directory used by tools like istanbul
+coverage/
+*.lcov
+
+# nyc test coverage
+.nyc_output
+
+# Dependency directories
+jspm_packages/
+
+# Optional npm cache directory
+.npm
+
+# Optional eslint cache
+.eslintcache
+
+# Microbundle cache
+.rpt2_cache/
+.rts2_cache_cjs/
+.rts2_cache_es/
+.rts2_cache_umd/
+
+# Optional REPL history
+.node_repl_history
+
+# Output of 'npm pack'
+*.tgz
+
+# Yarn Integrity file
+.yarn-integrity
+
+# dotenv environment variables file
+.env
+.env.test
+.env.local
+.env.development.local
+.env.test.local
+.env.production.local
+
+# parcel-bundler cache (https://parceljs.org/)
+.cache
+.parcel-cache
+
+# next.js build output
+.next
+
+# nuxt.js build output
+.nuxt
+
+# vuepress build output
+.vuepress/dist
+
+# Serverless directories
+.serverless/
+
+# FuseBox cache
+.fusebox/
+
+# DynamoDB Local files
+.dynamodb/
+
+# TernJS port file
+.tern-port