* feat: implement comprehensive help system with contextual icons
- Add HelpModal component with navigation sidebar and 7 help sections
- Add HelpButton component for main header controls
- Add ContextualHelpIcon component for contextual help throughout UI
- Add help icons to all major UI sections:
- Settings modals (Server Settings, General Settings)
- Sync button with update system help
- Tab headers (Available, Downloaded, Installed Scripts)
- FilterBar and CategorySidebar
- Add comprehensive help content covering:
- Server Settings: PVE server management, auth types, color coding
- General Settings: Save filters, GitHub integration, authentication
- Sync Button: Script metadata syncing explanation
- Available Scripts: Browsing, filtering, downloading
- Downloaded Scripts: Local script management and updates
- Installed Scripts: Auto-detection feature (primary focus), manual management
- Update System: Automatic/manual update process, release notes
- Improve VersionDisplay: remove 'Update Available' text, add 'Release Notes:' label
- Make help icons more noticeable with increased size
- Fix dark theme compatibility issues in help modal
* fix: resolve linting errors in HelpModal component
- Remove unused Filter import
- Fix unescaped entities by replacing apostrophes and quotes with HTML entities
- All linting errors resolved
* feat: implement release notes modal system
- Add getAllReleases API endpoint to fetch GitHub releases with notes
- Create ReleaseNotesModal component with localStorage version tracking
- Add sticky Footer component with release notes link
- Make version badge clickable to open release notes
- Auto-show modal after updates when version changes
- Track last seen version in localStorage to prevent repeated shows
- Highlight new version in modal when opened after update
- Add manual access via footer and version badge clicks
* fix: use nullish coalescing operator in ReleaseNotesModal
- Replace logical OR (||) with nullish coalescing (??) operator
- Fixes ESLint prefer-nullish-coalescing rule violation
- Ensures build passes successfully
