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/hero-tile.njk

@@ -0,0 +1,24 @@
+<section class="hero-tile" aria-label="Blog Mission & Overview">
+  <div class="hero-pretitle">TECHNICAL PUBLICATION REPOSITORY &bull; ~/NOTES/INDEX.MD</div>
+  <h1 class="hero-main-title">{{ heroTitle or site.description }}</h1>
+  <p class="hero-landing-text">
+    {{ heroText or "A fast, zero-bloat digital workshop detailing hardware reverse engineering, low-level POSIX environments, self-hosted infrastructure, and kernel security research. Designed for dense information retrieval." }}
+  </p>
+
+  <div class="filter-pills-row" aria-label="Topic Filters">
+    <a href="/" class="filter-tag-btn {% if not currentTag %}active{% endif %}">
+      [All Dispatches ({{ collections.posts.length }})]
+    </a>
+    {% for tag in collections.tagList %}
+      {% set tagCount = 0 %}
+      {% for post in collections.posts %}
+        {% if tag in (post.data.tags or []) %}
+          {% set tagCount = tagCount + 1 %}
+        {% endif %}
+      {% endfor %}
+      <span class="filter-tag-btn {% if currentTag == tag %}active{% endif %}">
+        [#{{ tag }}{% if tagCount > 0 %} ({{ tagCount }}){% endif %}]
+      </span>
+    {% endfor %}
+  </div>
+</section>