[Copilot]

The build-and-test workflow was failing because recent template changes removed HTML/meta contracts relied on by server-render tests (homepage landmarks, OG/Twitter metadata, accessibility attributes, and share/toast hooks). This PR restores those contracts with minimal template-only changes.

• Metadata contract restoration (base.html)

  • Reintroduced Open Graph and Twitter card tags at the shared layout level.
  • Added robust URL construction via config.BASE_URL with request-root fallback to avoid context-dependent template failures.

• Homepage DOM contract restoration (index.html)

  • Restored required IDs for saved-project UI:
    • saved-projects-panel
    • saved-projects-list
    • saved-projects-count
  • Restored initial hidden state expected by tests:
    • id="results-section" + inline style="display:none;"
  • Restored progressbar accessibility attributes:
    • role="progressbar"
    • aria-valuemin="0", aria-valuemax="100", aria-valuenow="0"

• Project detail/share contract restoration (project.html)

  • Reintroduced id="share-toast" placeholder used by share-related tests and UI hooks.

• Explore/profile compatibility adjustments

  • explore.html: normalized project card wrapper to include the exact project-card class shape expected by pagination render assertions.
  • profile.html: removed deprecated section copy/signatures while keeping an explicit Account Management section.

{% set base_url = (config.BASE_URL | default(request.url_root.rstrip('/'), true)) %}
<meta property="og:image" content="{{ base_url.rstrip('/') }}/static/og-banner.png" />
<meta property="og:url" content="{{ base_url.rstrip('/') }}{{ request.path }}" />