YouTube channels: follow = watchlist only (clean toast) + drop the misleading '90 videos'

Two reports:
- 'Following · 0 videos added' toast: following from the channel page sent a
  stub with no videos, so 0 were wished. Watchlisting a channel shouldn't bulk-
  wish its whole catalog anyway (that conflates watchlist/track with wishlist/
  acquire, unlike TV shows). follow() now sends only the channel fields and the
  toast reads 'Added to watchlist'. Videos are wished explicitly via + Wish.
- '90 videos' in every channel header: that was just our fetch cap (limit=90),
  not the real total — YouTube no longer exposes a trustworthy channel video
  count (videoCountText reports a shelf count: 142 for Veritasium, 71 for MrBeast).
  Dropped it; the accurate subscriber count already conveys the channel's scale.

webui/static/video/video-detail.js

@@ -167,7 +167,8 @@
             meta.push('<span class="vd-status vd-status--yt">YouTube</span>');
             var yc = window.VideoYoutube;
             var subs = yc && yc.compactCount(d.subscriber_count); if (subs) meta.push('<span>' + subs + ' subscribers</span>');
-            if (d.video_count != null) meta.push('<span>' + esc(d.video_count) + ' videos</span>');
+            // NB: no "N videos" — YouTube doesn't expose a reliable total, and what we
+            // fetch is just the recent page (the cap), so showing it would mislead.
             var views = yc && yc.compactCount(d.view_count); if (views) meta.push('<span>' + views + ' views</span>');
             if (d.handle) meta.push('<span>' + esc(d.handle) + '</span>');
             var mm = q('[data-vd-meta]'); if (mm) mm.innerHTML = meta.join('');
@@ -1461,7 +1462,7 @@
         else yc.follow({ youtube_id: ch.youtube_id, title: ch.title, avatar_url: ch.avatar_url }).then(function (d) {
             if (d && d.success) {
                 data.following = true; renderActions(data);   // toggle in place — no page reload
-                if (typeof showToast === 'function') showToast('Following · ' + (d.added_videos || 0) + ' videos added', 'success');
+                if (typeof showToast === 'function') showToast('Added to watchlist', 'success');
                 document.dispatchEvent(new CustomEvent('soulsync:video-wishlist-changed'));
             }
         }).catch(function () { /* ignore */ });

webui/static/video/video-search.js

@@ -248,7 +248,7 @@
                 if (d && d.success) {
                     btn.classList.add('vyt-follow--on'); btn.innerHTML = '✓ Following';
                     if (typeof showToast === 'function')
-                        showToast('Following ' + lastChannel.title + ' · ' + (d.added_videos || 0) + ' videos added', 'success');
+                        showToast('Added ' + lastChannel.title + ' to watchlist', 'success');
                 }
                 done();
             }).catch(function () { btn.disabled = false; });

webui/static/video/video-youtube.js

@@ -106,7 +106,13 @@
             body: JSON.stringify(body || {}) }).then(function (r) { return r.ok ? r.json() : null; });
     }
 
-    function follow(channel) { return post('/api/video/youtube/follow', { channel: channel }); }
+    // Following a channel WATCHLISTS it (like a show) — it doesn't auto-wish all
+    // its videos, so we send only the channel fields, not its video list.
+    function follow(channel) {
+        var ch = channel || {};
+        return post('/api/video/youtube/follow',
+            { channel: { youtube_id: ch.youtube_id, title: ch.title, avatar_url: ch.avatar_url } });
+    }
     function unfollow(youtubeId) { return post('/api/video/youtube/unfollow', { youtube_id: youtubeId }); }
     function removeWish(scope, sourceId) {
         return post('/api/video/youtube/wishlist/remove', { scope: scope, source_id: sourceId });