feat: implement dynamic Eleventy tiling blog, modular CSS, and agent customizations

- Add project foundation README.md and root AGENTS.md for pair programming
- Configure .agents/ rules and skills for Eleventy tiling and Obsidian publishing
- Decompose monolithic styles into modular tokens, reset, layout, and component CSS
- Implement Nunjucks layout inheritance (base.njk, post.njk, page.njk) and reusable partials
- Configure Eleventy 3 with markdown-it-anchor, syntax highlighting, and dynamic collections
- Migrate sample prototypes into dynamic dispatches lander, gateway, and Markdown posts
- Add multi-stage Dockerfile and clean-URL nginx.conf for production serving

src/_includes/partials/featured-card.njk

@@ -0,0 +1,62 @@
+{% set featured = null %}
+{% for p in collections.posts %}
+  {% if p.data.featured and not featured %}
+    {% set featured = p %}
+  {% endif %}
+{% endfor %}
+{% if not featured and collections.posts.length > 0 %}
+  {% set featured = collections.posts[0] %}
+{% endif %}
+
+{% if featured %}
+<section class="tile" aria-label="Featured Technical Dispatch">
+  <header class="tile-header">
+    <div class="tile-title">
+      <span class="status-indicator"></span>
+      FEATURED DISPATCH
+    </div>
+    <span class="tile-meta">{{ (featured.data.tags | filterTagList)[0] | default('SYSTEMS') | upper }} &bull; {{ featured.templateContent | readingTime(featured.data.readingTime) }}</span>
+  </header>
+
+  <div class="featured-card-body">
+    <div class="featured-badge-row">
+      <span class="badge-pinned">[FEATURED DEEP DIVE]</span>
+      <time datetime="{{ featured.date | isoDate }}">{{ featured.date | postDate }}</time>
+    </div>
+
+    <h2 style="margin: 0; font-size: inherit;">
+      <a href="{{ featured.url }}" class="featured-article-title">{{ featured.data.title }}</a>
+    </h2>
+
+    <p class="featured-prose">
+      {{ featured.data.excerpt }}
+    </p>
+
+    <!-- Terminal Code Preview Snippet -->
+    <div class="terminal-code-box">
+      <div class="code-titlebar">
+        <span class="code-title">
+          <span style="color: var(--accent-cyan);">&gt;</span>
+          <span>flashrom_read.sh</span>
+        </span>
+        <span>POSIX sh</span>
+      </div>
+      <div class="code-content">
+        <pre><code class="language-bash"># Probe SPI flash chip and dump 16MB image
+flashrom -p ch341a_spi -r firmware_dump.bin -V
+# Verify checksums across consecutive reads
+sha256sum dump1.bin dump2.bin</code></pre>
+      </div>
+    </div>
+
+    <div class="featured-cta-row">
+      <div class="tag-cluster">
+        {% for tag in featured.data.tags | filterTagList %}
+          <span class="tag-chip">#{{ tag }}</span>
+        {% endfor %}
+      </div>
+      <a href="{{ featured.url }}" class="cta-button">READ FULL WRITEUP &rarr;</a>
+    </div>
+  </div>
+</section>
+{% endif %}