Phase 19: notifications tab with mark-read support

Notifications tab now fully functional. Each notification shows a type
icon, colored left border (gold=level_up, green=objective, amber=warning,
red=expired, blue=season), bold title when unread, body text, timestamp,
and a per-item Mark read button for persistent notifications.

Header badge and the unread count label now use unread_count from the
Core response rather than total notification count.

A Mark all read button calls POST /notifications/read-all and refreshes
the list. Per-item PATCH /notifications/:id/read hides the button and
dims the card on success.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/dashboard.html

@@ -640,6 +640,10 @@ h2 { font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.05em;
 
 <!-- ── Notifications tab ─────────────────────────────────────────────────── -->
 <div id="tab-notifications" class="tab-panel">
+  <div style="display:flex;justify-content:space-between;align-items:center;margin-bottom:16px">
+    <h2 style="margin:0">Notifications <span id="notif-unread-label" style="font-size:0.85rem;color:#8b949e;font-weight:400"></span></h2>
+    <button class="btn btn-secondary btn-sm" onclick="markAllNotificationsRead()">Mark all read</button>
+  </div>
   <div id="notif-list" class="notif-list"><span class="loading">Loading…</span></div>
 </div>
 
@@ -2076,31 +2080,86 @@ async function toggleEvent(eventId, activate, btn) {
 
 // ── Notifications ─────────────────────────────────────────────────────────────
 
+const NOTIF_ICONS = {
+  level_up: '⬆',
+  objective_complete: '✓',
+  loan_expiring: '⏳',
+  loan_expired: '✕',
+  season_end: '🏆',
+  season_ending: '⌛',
+};
+
+function notifKindLabel(type) {
+  return {
+    level_up: 'Level Up',
+    objective_complete: 'Objective',
+    loan_expiring: 'Loan Warning',
+    loan_expired: 'Loan Expired',
+    season_end: 'Season',
+    season_ending: 'Season',
+  }[type] || type;
+}
+
 async function loadNotifications() {
   try {
     const data = await api('GET', '/notifications');
     const notifs = data.notifications || [];
-    el('notif-badge').textContent = notifs.length > 0 ? ` (${notifs.length})` : '';
+    const unread = data.unread_count ?? notifs.filter(n => !n.is_read).length;
+    el('notif-badge').textContent = unread > 0 ? ` (${unread})` : '';
+    if (el('notif-unread-label')) {
+      el('notif-unread-label').textContent = unread > 0 ? `${unread} unread` : 'all read';
+    }
     if (!notifs.length) {
-      el('notif-list').innerHTML = '<span class="empty">No notifications right now.</span>';
+      el('notif-list').innerHTML = '<span class="empty">No notifications yet. Play matches, complete objectives, and level up to generate notifications.</span>';
       return;
     }
     el('notif-list').innerHTML = notifs.map(n => `
-      <div class="notif-item ${n.type}">
-        <div class="notif-title">${n.title}</div>
-        <div class="notif-msg">${n.message}</div>
+      <div class="notif-item ${n.type || ''} ${n.is_read ? 'notif-read' : 'notif-unread'}"
+           style="display:flex;gap:12px;align-items:flex-start;padding:12px 14px;
+                  background:${n.is_read ? '#0d1117' : '#161b22'};border-radius:8px;
+                  margin-bottom:8px;border-left:3px solid ${notifBorderColor(n.type)}">
+        <span style="font-size:1.2rem;min-width:24px;text-align:center">${NOTIF_ICONS[n.type] || '•'}</span>
+        <div style="flex:1">
+          <div style="display:flex;justify-content:space-between;align-items:center;gap:8px">
+            <div class="notif-title" style="font-weight:${n.is_read ? '400' : '600'};color:${n.is_read ? '#8b949e' : '#f0f6fc'}">${n.title}</div>
+            <span style="font-size:0.7rem;color:#6e7681;white-space:nowrap">${notifKindLabel(n.type)}</span>
+          </div>
+          <div class="notif-body" style="font-size:0.82rem;color:#8b949e;margin-top:3px">${n.body || n.message || ''}</div>
+          ${n.created_at ? `<div style="font-size:0.7rem;color:#6e7681;margin-top:4px">${new Date(n.created_at).toLocaleString()}</div>` : ''}
+        </div>
+        ${n.id && !n.is_read ? `<button class="btn btn-secondary btn-sm" onclick="markNotificationRead('${n.id}', this)" style="align-self:center;white-space:nowrap">Mark read</button>` : ''}
       </div>`).join('');
   } catch (e) { el('notif-list').innerHTML = `<div class="error-msg">${e.message}</div>`; }
 }
 
+function notifBorderColor(type) {
+  return { level_up: '#f5a623', objective_complete: '#3fb950', loan_expiring: '#d29922', loan_expired: '#f85149', season_end: '#58a6ff', season_ending: '#d29922' }[type] || '#30363d';
+}
+
+async function markNotificationRead(id, btn) {
+  btn.disabled = true;
+  try {
+    await api('PATCH', `/notifications/${id}/read`);
+    loadNotifications();
+  } catch (e) { showToast(e.message, true); btn.disabled = false; }
+}
+
+async function markAllNotificationsRead() {
+  try {
+    await api('POST', '/notifications/read-all');
+    showToast('All notifications marked as read');
+    loadNotifications();
+  } catch (e) { showToast(e.message, true); }
+}
+
 // ── Init ─────────────────────────────────────────────────────────────────────
 
 window.addEventListener('DOMContentLoaded', () => {
   loadClub();
   // Load notification badge count silently
   api('GET', '/notifications').then(d => {
-    const n = (d.notifications || []).length;
-    el('notif-badge').textContent = n > 0 ? ` (${n})` : '';
+    const unread = d.unread_count ?? (d.notifications || []).filter(n => !n.is_read).length;
+    el('notif-badge').textContent = unread > 0 ? ` (${unread})` : '';
   }).catch(() => {});
 });
 </script>