feat: implement comprehensive UI/UX improvements

This commit implements 7 requested improvements:

1. Add footer component to all pages
   - Created reusable AppFooter component
   - Added to layout.tsx with flex-1 main container
   - Includes links to Legal, Disclaimer, Imprint, GitHub

2. Change search highlight from yellow to more discreet color
   - Updated mark styling with purple theme colors
   - Uses color-mix for theme-aware transparency
   - Added subtle border-bottom for better visibility

3. Strip markdown from search results
   - Created stripMarkdown function
   - Removes HTML tags, markdown links, images, formatting
   - Shows clean text descriptions only

4. Add page number links to pagination
   - Created getPageNumbers function with smart ellipsis
   - Shows current page ±2 pages with first/last always visible
   - Example: 1 ... 5 6 [7] 8 9 ... 20

5. Adjust README badge display to be inline
   - Custom marked renderer detects badges (shields.io, badgen, etc.)
   - Applies inline-block with !my-0 !mx-1 align-middle classes
   - Badges now display inline in paragraph flow

6. Fix relative image URLs in READMEs
   - Custom image renderer converts relative to absolute GitHub URLs
   - Handles ./path and path patterns
   - Converts to raw.githubusercontent.com URLs
   - Also handles /blob/ URLs conversion

7. Fix command menu highlight contrast
   - Reuses mark styling from search highlights
   - Consistent purple theme colors across app

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

app/readme/[owner]/[repo]/page.tsx

@@ -92,7 +92,7 @@ export default async function ReadmePage({ params }: PageProps) {
             </div>
           }
         >
-          <ReadmeViewer content={data.content} />
+          <ReadmeViewer content={data.content} repositoryUrl={data.metadata.url} />
         </Suspense>
       </div>
     </div>