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/storage/queries.go

@@ -380,6 +380,67 @@ func ListRecentlyPosted(limit int) ([]Story, error) {
 	return out, rows.Err()
 }
 
+// TrendingStories returns the most-read classified stories (real channels only)
+// counting views recorded on or after sinceDay (a unix day number), newest-ish
+// as a tiebreak. Used for the home page's "popular this week" rail. Stories with
+// no views in the window don't appear, so the rail is empty until reads exist.
+func TrendingStories(limit int, sinceDay int64) ([]Story, error) {
+	rows, err := Get().Query(
+		`SELECT s.id, s.guid, s.headline, s.lede, s.image_url, s.article_url, s.source, s.platforms, s.channel, s.paywalled, s.seen_at,
+		        EXISTS(SELECT 1 FROM post_log p WHERE p.guid = s.guid) AS posted
+		 FROM stories s
+		 JOIN story_views v ON v.story_id = s.id
+		 WHERE s.classified = 1
+		   AND s.channel IS NOT NULL
+		   AND s.channel NOT IN ('_discarded', '_duplicate')
+		   AND v.day >= ?
+		 GROUP BY s.id
+		 ORDER BY SUM(v.views) DESC, COALESCE(s.published_at, s.seen_at) DESC
+		 LIMIT ?`, sinceDay, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Story
+	for rows.Next() {
+		var s Story
+		if err := rows.Scan(&s.ID, &s.GUID, &s.Headline, &s.Lede, &s.ImageURL, &s.ArticleURL, &s.Source, &s.Platforms, &s.Channel, &s.Paywalled, &s.SeenAt, &s.Posted); err != nil {
+			return nil, err
+		}
+		out = append(out, s)
+	}
+	return out, rows.Err()
+}
+
+// StoryContentLengths returns the captured article text length (in characters)
+// for the given story ids, as a map keyed by id. Used to estimate a "N min read"
+// chip without transferring the full body: only LENGTH(content) crosses the
+// wire. Ids with no captured content are absent (treated as zero by callers).
+func StoryContentLengths(ids []int64) map[int64]int {
+	out := make(map[int64]int, len(ids))
+	if len(ids) == 0 {
+		return out
+	}
+	ph, args := intInClause(ids)
+	rows, err := Get().Query(
+		`SELECT id, LENGTH(content) FROM stories
+		 WHERE id IN (`+ph+`) AND content IS NOT NULL AND content <> ''`, args...)
+	if err != nil {
+		slog.Error("story content lengths query failed", "err", err)
+		return out
+	}
+	defer rows.Close()
+	for rows.Next() {
+		var id, n int64
+		if err := rows.Scan(&id, &n); err != nil {
+			slog.Error("scan content length failed", "err", err)
+			continue
+		}
+		out[id] = int(n)
+	}
+	return out
+}
+
 // CountClassifiedByChannel returns how many classified stories exist for a channel.
 func CountClassifiedByChannel(channel string) (int, error) {
 	var n int