Add agentic workflows page to website

Add a new /workflows/ page for browsing agentic workflow definitions
with search, trigger/tag filters, and sorting. Follows the same
patterns as the existing hooks page.

New files:
- website/src/pages/workflows.astro
- website/src/scripts/pages/workflows.ts

Updated files:
- BaseLayout.astro: add Workflows nav link
- index.astro: add Workflows card to homepage
- pages/index.ts: add workflows to counts
- utils.ts: add workflow type to icons, labels, and getResourceType

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

website/src/pages/index.astro

@@ -57,6 +57,14 @@ const base = import.meta.env.BASE_URL;
             </div>
             <div class="card-count" data-count="hooks" aria-label="Hook count">-</div>
           </a>
+          <a href={`${base}workflows/`} class="card card-with-count" id="card-workflows">
+            <div class="card-icon" aria-hidden="true">⚡</div>
+            <div class="card-content">
+              <h3>Workflows</h3>
+              <p>AI-powered automations for GitHub Actions</p>
+            </div>
+            <div class="card-count" data-count="workflows" aria-label="Workflow count">-</div>
+          </a>
           <a href={`${base}plugins/`} class="card card-with-count" id="card-plugins">
             <div class="card-icon" aria-hidden="true">🔌</div>
             <div class="card-content">