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/layout.tsx

@@ -6,6 +6,7 @@ import { Toaster } from '@/components/ui/sonner'
 import { WorkerProvider } from '@/components/providers/worker-provider'
 import { CommandProvider } from '@/components/providers/command-provider'
 import { AppHeader } from '@/components/layout/app-header'
+import { AppFooter } from '@/components/layout/app-footer'
 import { ThemeProvider } from 'next-themes'
 
 const inter = Inter({ subsets: ['latin'] })
@@ -203,8 +204,11 @@ export default function RootLayout({
         >
           <WorkerProvider>
             <CommandProvider>
-              <AppHeader />
-              {children}
+              <div className="flex min-h-screen flex-col">
+                <AppHeader />
+                <main className="flex-1">{children}</main>
+                <AppFooter />
+              </div>
             </CommandProvider>
           </WorkerProvider>
           <Toaster />