Refactor workflow-lite-planex documentation to standardize phase naming and improve clarity

- Updated phase references in SKILL.md and 01-lite-plan.md to use "LP-Phase" prefix for consistency.
- Added critical context isolation note in 01-lite-plan.md to clarify phase invocation rules.
- Enhanced execution process descriptions to reflect updated phase naming conventions.

Improve error handling in frontend routing

- Introduced ChunkErrorBoundary component to handle lazy-loaded chunk load failures.
- Wrapped lazy-loaded routes with error boundary and suspense for better user experience.
- Created PageSkeleton component for loading states in lazy-loaded routes.

Sanitize header values in notification routes

- Added regex validation for header values to prevent XSS attacks by allowing only printable ASCII characters.

Enhance mobile responsiveness in documentation styles

- Updated CSS breakpoints to use custom properties for better maintainability.
- Improved layout styles across various components to ensure consistent behavior on mobile devices.

docs/.vitepress/theme/styles/custom.css

@@ -86,12 +86,10 @@
   padding: 0 !important;
   margin: 0 !important;
   max-width: 100vw !important;
-  overflow-x: hidden !important;
 }
 
 .Layout:has(.pro-home) {
   max-width: 100vw !important;
-  overflow-x: hidden !important;
 }
 
 /* Ensure VPNav doesn't cause overflow */
@@ -113,7 +111,6 @@
   padding: 0 !important;
   margin: 0 !important;
   width: 100% !important;
-  overflow-x: hidden !important;
   box-sizing: border-box !important;
 }