docs(website): update navigation links to philosophy section

Change header and footer "Features" links to point to the new
"#philosophy" section and rename them to "Why Blade" to align
with the recent landing page redesign.

src/layouts/BaseLayout.astro

@@ -57,7 +57,7 @@ const { title, description = "AI-Native code editor built with Rust and Tauri. F
             <img src="/zblade-logo.png" alt="Zaguán Blade" class="logo-image" />
           </a>
           <nav class="nav">
-            <a href="/#features">Features</a>
+            <a href="/#philosophy">Why Blade</a>
             <a href="/docs">Docs</a>
             <a href="/blog">Blog</a>
             <a href="/changelog">Changelog</a>
@@ -79,7 +79,7 @@ const { title, description = "AI-Native code editor built with Rust and Tauri. F
           </div>
           <div class="footer-section">
             <h4>Product</h4>
-            <a href="/#features">Features</a>
+            <a href="/#philosophy">Why Blade</a>
             <a href="/docs">Documentation</a>
             <a href="/blog">Blog</a>
             <a href="/changelog">Changelog</a>