refactor: Update timeout values and remove session recovery steps

fix: Fix E2E test failures and improve session initialization

feat: Implement browser state restoration using localStorage

Add audio recovery feature and enhance audio state management

refactor: Clean up code formatting and improve readability across multiple files

feat: Enhance URL extraction and text management features

Add URL extraction feature and related tests

Implement global VOICEVOX Core manager for shared audio generation across users

Refactor unit tests for SessionManager and TextProcessor classes