Video once-per-day dedup + featured gold border & spacing

- Video watch-to-earn: a member can no longer re-earn from the same video the
  same day. New video_seen table (dual-mode); serveVideo excludes today's
  already-watched videos; videowatch double-checks before crediting.
- Featured card: equal top/bottom margin (no longer touches the stat cards) and
  a gold border on the card + the rotating link.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

db.js

@@ -142,6 +142,14 @@ async function bootstrap() {
   // per-account chat settings: availability toggle (default on) + muted-member list (JSON emails)
   await alterSafe('ALTER TABLE accounts ADD COLUMN chat_available TINYINT NOT NULL DEFAULT 1');
   await alterSafe('ALTER TABLE accounts ADD COLUMN chat_mutes VARCHAR(4000) NULL');
+  await q(`CREATE TABLE IF NOT EXISTS video_seen (
+    email VARCHAR(190) NOT NULL,
+    campaign_id INT NOT NULL,
+    day CHAR(10) NOT NULL,
+    ts BIGINT NOT NULL,
+    UNIQUE KEY uq_vseen (email, campaign_id, day),
+    INDEX (email, day)
+  ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4`);
   await q(`CREATE TABLE IF NOT EXISTS ad_reports (
     id INT AUTO_INCREMENT PRIMARY KEY,
     campaign_id INT NOT NULL,