Apply LogoPack website branding

[EzerchE]

Updates the website branding assets using the accepted CouchMode LogoPack. This is website-only and does not touch app, backend, installer, tray, or beta.31 work.

Changes:

• Replaces the temporary header/footer mark with the LogoPack dark lockup
• Adds new favicon SVG/PNG/apple-touch assets and updates head links
• Updates the webmanifest icon references
• Replaces the old favicon.ico fallback and removes old icon-192/icon-512 assets
• Updates the public OG image to remove the old temporary mark
• Updates Brand JSON-LD logo to the new apple-touch icon

Validation:

• npm run build passes
• Public output guardrail scan is clean
• No .exe href introduced
• Desktop header logo renders without horizontal overflow
• Mobile header keeps nav/CTA hidden and does not overflow
• Brand/favicon/manifest/OG assets return 200 locally

Out of scope:

• No app icon, tray icon, installer icon, beta.31 app build, backend, patch notes, or public installer download changes