Changelog: Was ist neu? Button + Unread-Tracking

backend/src/db.js

@@ -342,6 +342,15 @@ const clCols = db.prepare("PRAGMA table_info(changelog)").all().map(r => r.name)
 if (clCols.length && !clCols.includes('build_time'))
   db.exec("ALTER TABLE changelog ADD COLUMN build_time TEXT DEFAULT NULL");
 
+if (!db.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name='changelog_reads'").get()) {
+  db.exec(`
+    CREATE TABLE changelog_reads (
+      user_id    INTEGER PRIMARY KEY REFERENCES users(id) ON DELETE CASCADE,
+      last_read  DATETIME DEFAULT NULL
+    )
+  `);
+}
+
 // ── Push-Zeitplaner ───────────────────────────────────────────────────────────
 if (!db.prepare("SELECT name FROM sqlite_master WHERE type='table' AND name='push_schedules'").get()) {
   db.exec(`

backend/src/routes/dashboard.js

@@ -211,6 +211,21 @@ router.get('/changelog', authenticate, (req, res) => {
   res.json(db.prepare('SELECT * FROM changelog ORDER BY created_at DESC').all());
 });
 
+router.get('/changelog/unread', authenticate, (req, res) => {
+  const u = req.user.id;
+  const lastRead = db.prepare('SELECT last_read FROM changelog_reads WHERE user_id=?').get(u)?.last_read;
+  const count = lastRead
+    ? db.prepare('SELECT COUNT(*) c FROM changelog WHERE created_at > ?').get(lastRead).c
+    : db.prepare('SELECT COUNT(*) c FROM changelog').get().c;
+  res.json({ unread: count });
+});
+
+router.post('/changelog/read', authenticate, (req, res) => {
+  db.prepare(`INSERT OR REPLACE INTO changelog_reads (user_id, last_read) VALUES (?, datetime('now','localtime'))`)
+    .run(req.user.id);
+  res.json({ ok: true });
+});
+
 router.post('/changelog', authenticate, requireAdmin, (req, res) => {
   const { version, title, body, build_time } = req.body;
   if (!version?.trim() || !title?.trim()) return res.status(400).json({ error: 'Version und Titel erforderlich' });