refactor(blog): drop the full archive, the topic hubs already carry it

The "All articles" list existed because pagination alone left 18 of the 26
posts three or more clicks from the home page. The topic hubs were added for
that same complaint and solved it: all 33 live posts sit in at least one of
the 12 hubs, the hubs are unpaginated, and their chips are in the /blog/
sidebar. Nothing is orphaned without the archive.

What it was still doing was rendering on every paginated page, so
/blog/page/4/ was five cards plus the same 33-link list — the archive was the
bulk of seven near-identical URLs, and pagination was decorative.

The Blog node on /blog/ still enumerates all 33 BlogPosting entries, so the
machine-readable full list is unchanged. Search KPI is byte-identical either
way: P@1 macro 52.3%, micro 61.2%, recall@6 90.1%.

Author: Mikhus

src/_shared/css/base.css

@@ -261,15 +261,15 @@ a.card:hover { border-color: var(--accent); text-decoration: none; }
      explicit MOBILE size that this rule was silently overriding — .prose h1/h2
      (prose.css:195-196), .hero h1 (org/index.html) and .fx-h2/.fx-thanks h2
      (flux.css:142,118) — so those media queries had no effect at all. The
-     component ones were the visible damage: .aside-box h2 and .blog-archive h2
-     are 13.5px uppercase mono labels and were rendering at 29.5px, so every blog
-     post showed "Written by" and the sidebar headings at section-heading size,
+     component ones were the visible damage: .aside-box h2 is a 13.5px uppercase
+     mono label and was rendering at 29.5px, so every blog post showed
+     "Written by" and the sidebar headings at section-heading size,
      and .card/.post-card titles were as large as the sections containing them.
 
      .fx-h1 is deliberately NOT excluded: the com heroes carry an inline 44-46px
      that beats flux.css's own 38px mobile rule, so this is what shrinks them. */
   h1:not(.prose h1, .hero h1) { font-size: 38.5px !important; }
-  h2:not(.prose h2, .card h2, .post-card h2, .aside-box h2, .blog-archive h2, .fx-h2, .fx-thanks h2) { font-size: 29.5px !important; }
+  h2:not(.prose h2, .card h2, .post-card h2, .aside-box h2, .fx-h2, .fx-thanks h2) { font-size: 29.5px !important; }
 }
 /* 2 × 2. Four columns fit until 656px (4 × 127 + 3 × 28 gap + 64 padding), so the fold
    is here rather than at the 760px content breakpoint: between the two the footer keeps
@@ -404,16 +404,6 @@ a.topic-chip:hover { border-color: var(--accent); color: var(--accent); }
 .topic-chip > span { color: var(--muted); font-size: 11.5px; }
 .topic-chip--flat { color: var(--muted); }
 
-/* ---- blog archive ------------------------------------------------------ */
-.blog-archive { margin-top: 44px; padding-top: 28px; border-top: 1px solid var(--line); }
-.blog-archive h2 { font-family: var(--font-mono); font-size: 13.5px; letter-spacing: .16em; text-transform: uppercase; color: var(--muted); margin: 0 0 18px; font-weight: 600; }
-.blog-archive h3 { font-family: var(--font-mono); font-size: 15px; color: var(--muted); margin: 22px 0 8px; font-weight: 500; }
-.archive-list { list-style: none; margin: 0; padding: 0; }
-.archive-list li { display: flex; align-items: baseline; gap: 10px; padding: 5px 0; border-bottom: 1px dashed color-mix(in srgb, var(--line) 60%, transparent); }
-.archive-list a { color: var(--ink); text-decoration: none; font-size: 15.5px; }
-.archive-list a:hover { color: var(--accent); }
-.archive-list .meta { font-family: var(--font-mono); font-size: 12.5px; color: var(--muted); margin-left: auto; white-space: nowrap; }
-
 /* ---- cookie-consent bar (_includes/consent.html, js/consent.js) ----
    Fixed to the bottom: the choice has to stay reachable however far the page is
    scrolled, and a bar cannot be scrolled past the way an in-flow notice can. z-index

src/org/blog/index.html

@@ -49,35 +49,6 @@ <h2>{{ post.data.title }}</h2>
         {% if pagination.href.next %}<a href="{{ pagination.href.next }}" aria-label="Next page">→</a>{% else %}<span class="disabled">→</span>{% endif %}
       </nav>
       {%- endif -%}
-
-      {%- comment -%}
-      Full archive, on every paginated page.
-
-      Pagination alone left 18 of the 26 posts three or more clicks from the home
-      page — /blog/ surfaced 5 cards plus the 8 newest in the sidebar, and nothing
-      else linked the rest. Weakly linked URLs are exactly what lands in GSC's
-      "Discovered — currently not indexed". Listing every post here puts all of
-      them two clicks from the home page, and grouping by year gives the list a
-      structure a flat dump of 26 links would not have.
-      {%- endcomment -%}
-      <section class="blog-archive" aria-labelledby="all-articles">
-        <h2 id="all-articles">All articles</h2>
-        {%- assign lastYear = "" -%}
-        {%- for post in collections.posts -%}
-        {%- assign year = post.date | date: "%Y" -%}
-        {%- if year != lastYear -%}
-        {%- unless lastYear == "" %}</ul>{% endunless %}
-        <h3>{{ year }}</h3>
-        <ul class="archive-list">
-        {%- assign lastYear = year -%}
-        {%- endif -%}
-          <li>
-            <a href="{{ post.url }}">{{ post.data.title }}</a>
-            <span class="meta">{{ post.date | date: "%b %-d" }}</span>
-          </li>
-        {%- endfor -%}
-        {%- unless lastYear == "" %}</ul>{% endunless %}
-      </section>
     </div>
 
     <!-- SIDEBAR -->