Bug-Reports, Devlog-Threads und Watchdog

- /bug (alle Member): erstellt Gitea-Issue inkl. Screenshot-Upload als Asset;
  bug_reports-Tabelle für den Rückkanal — Issue geschlossen (issues-Webhook)
  → DM an den Reporter
- Auto-Thread '💬 Devlog <Datum>' unter jedem Devlog-Post (Setting, Default an)
- Watchdog: prüft Setting watchdog_urls alle 2 min, DM an Admin nach 2 Fails
  in Folge + Entwarnung mit Downtime-Dauer
- Setup-Seite: Bug-Repo, Threads-Toggle, Watchdog-URLs; Env GITEA_API_TOKEN/GITEA_URL

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

src/db.js

@@ -79,6 +79,40 @@ db.exec(`
     }
 }
 
+// Bug-Reports aus Discord (/bug) — für den Rückkanal (Issue geschlossen → DM)
+db.exec(`
+    CREATE TABLE IF NOT EXISTS bug_reports (
+        repo            TEXT NOT NULL,
+        issue_number    INTEGER NOT NULL,
+        discord_user_id TEXT NOT NULL,
+        title           TEXT,
+        created_at      TEXT NOT NULL DEFAULT (datetime('now')),
+        PRIMARY KEY (repo, issue_number)
+    );
+`);
+
+const insertBugReport = db.prepare(`
+    INSERT OR REPLACE INTO bug_reports (repo, issue_number, discord_user_id, title)
+    VALUES (@repo, @issue_number, @discord_user_id, @title)
+`);
+const getBugReportStmt = db.prepare(
+    'SELECT * FROM bug_reports WHERE repo = ? AND issue_number = ?'
+);
+const deleteBugReportStmt = db.prepare(
+    'DELETE FROM bug_reports WHERE repo = ? AND issue_number = ?'
+);
+
+export function saveBugReport(report) {
+    insertBugReport.run(report);
+}
+
+/** Report holen und direkt entfernen (einmalige Benachrichtigung) */
+export function takeBugReport(repo, issueNumber) {
+    const row = getBugReportStmt.get(repo, issueNumber);
+    if (row) deleteBugReportStmt.run(repo, issueNumber);
+    return row ?? null;
+}
+
 // Laufzeit-Einstellungen (Settings-Seite im Webinterface) — überschreiben Env-Defaults
 db.exec('CREATE TABLE IF NOT EXISTS settings (key TEXT PRIMARY KEY, value TEXT NOT NULL)');
 const getSettingStmt = db.prepare('SELECT value FROM settings WHERE key = ?');