Add read-only web UI

Serves Pete's classified-story archive over HTTP alongside the Matrix
bot. Three sections (gaming/tech/politics), Animal-Crossing-vibe Tailwind
templates, day/night palette driven by the visitor's browser clock.
Web port configurable via web.listen_addr and ${PETE_WEB_PORT} in
docker-compose. Tailwind built in a node stage in the Dockerfile so
deployments don't need node at runtime.

internal/storage/queries.go

@@ -270,6 +270,41 @@ func GetNewestPostableStoryByChannel(channel string) (*Story, error) {
 	return &s, nil
 }
 
+// ListClassifiedByChannel returns up to `limit` classified stories routed to a
+// real channel, newest first, with optional offset for pagination. Sentinel
+// channels (_discarded, _duplicate) are excluded.
+func ListClassifiedByChannel(channel string, limit, offset int) ([]Story, error) {
+	rows, err := Get().Query(
+		`SELECT guid, headline, lede, image_url, article_url, source, feed_hint, platforms, channel, seen_at
+		 FROM stories
+		 WHERE classified = 1
+		   AND channel = ?
+		 ORDER BY seen_at DESC
+		 LIMIT ? OFFSET ?`, channel, limit, offset)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+	var out []Story
+	for rows.Next() {
+		var s Story
+		if err := rows.Scan(&s.GUID, &s.Headline, &s.Lede, &s.ImageURL, &s.ArticleURL, &s.Source, &s.FeedHint, &s.Platforms, &s.Channel, &s.SeenAt); err != nil {
+			return nil, err
+		}
+		out = append(out, s)
+	}
+	return out, rows.Err()
+}
+
+// CountClassifiedByChannel returns how many classified stories exist for a channel.
+func CountClassifiedByChannel(channel string) (int, error) {
+	var n int
+	err := Get().QueryRow(
+		`SELECT COUNT(*) FROM stories WHERE classified = 1 AND channel = ?`,
+		channel).Scan(&n)
+	return n, err
+}
+
 // GetRoundRobinState returns the last channel posted by the round-robin
 // scheduler and the timestamp of that tick. Empty string + 0 if no state yet.
 func GetRoundRobinState() (lastChannel string, lastTickAt int64, err error) {