Add per-story views, trending, and reader reading-experience upgrades

Surface read counts and sharpen the reader:
- story_views table + RecordStoryView on /api/article (background,
  filter-guarded); "Popular this week" home rail via TrendingStories;
  read-count badge and reading-time chip decorated onto every listing
- reader: signed-in-only read-aloud (TTS), native share/copy, and an
  Aa typography popover (size/serif/sepia) persisted per device
- real alt text on card/reader/related/search images; time-of-day Pete
  greeting on the home hero
- harden exec() to skip (not panic) on a nil DB so background writes
  can't crash on a closed handle

Tests: story_views_test.go, trending_test.go. Suite green, CSS rebuilt.

internal/web/templates/_card.html

@@ -20,7 +20,7 @@
   </span>
   {{if .Story.ImageURL}}
   <div class="aspect-[16/10] w-full overflow-hidden bg-[color:var(--ink)]/5">
-    <img src="{{thumb .Story.ImageURL}}" alt="" loading="lazy" decoding="async"
+    <img src="{{thumb .Story.ImageURL}}" alt="{{.Story.Headline}}" loading="lazy" decoding="async"
          class="h-full w-full object-cover group-hover:scale-105 transition duration-500">
   </div>
   {{end}}
@@ -37,6 +37,10 @@
       </span>
       {{end}}
       <span class="text-[color:var(--ink)]/50">{{timeAgo .Story.SeenAt}}</span>
+      {{if .Story.ReadMins}}<span class="text-[color:var(--ink)]/45">· {{.Story.ReadMins}} min read</span>{{end}}
+      {{if .Story.Views}}<span class="ml-auto inline-flex items-center gap-1 text-[color:var(--ink)]/45 tabular-nums" title="{{.Story.Views}} reads">
+        <svg viewBox="0 0 24 24" width="13" height="13" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><path d="M1 12s4-7 11-7 11 7 11 7-4 7-11 7-11-7-11-7z"></path><circle cx="12" cy="12" r="3"></circle></svg>
+        {{.Story.Views}}</span>{{end}}
     </div>
     <h3 class="font-display text-lg font-semibold leading-snug group-hover:underline underline-offset-2 decoration-theme-{{.Theme}}">
       {{.Story.Headline}}