Add Postfach page to manually assign unlinked e-mails

Incoming e-mails that IMAP matching could not link to an application
(bewerbung_id IS NULL) were invisible. Add a dedicated page listing
them with a dropdown of existing applications to assign each one by
hand. A header badge on every page shows the count of unlinked e-mails
via a small /api/emails/unassigned-count endpoint.

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

server.js

@@ -1181,6 +1181,76 @@ initializeDatabase().then(() => {
     }
   });
 
+  // ---------------------------------------------------------------------------
+  //  Postfach: incoming e-mails that landed in the inbox but could not be
+  //  matched to an application automatically. The user assigns them by hand.
+  // ---------------------------------------------------------------------------
+
+  // Page listing all e-mails with no bewerbung_id, plus every application as
+  // assignment target.
+  app.get('/postfach', async (req, res) => {
+    try {
+      const emails = await dbAll(
+        `SELECT * FROM emails WHERE bewerbung_id IS NULL ORDER BY datetime(email_date) DESC, id DESC`
+      );
+      if (emails.length) {
+        const eIds = emails.map((e) => e.id);
+        const atts = await dbAll(
+          `SELECT id, email_id, name, mime FROM email_anhaenge WHERE email_id IN (${eIds.map(() => '?').join(',')})`,
+          eIds
+        );
+        const byEmail = {};
+        atts.forEach((a) => { (byEmail[a.email_id] = byEmail[a.email_id] || []).push(a); });
+        emails.forEach((e) => { e.anhaenge = byEmail[e.id] || []; });
+      }
+      // Applications the user can assign an e-mail to (newest first).
+      const bewerbungen = await dbAll(
+        `SELECT id, firma, stelle, ort, datum FROM bewerbungen ORDER BY datum DESC, created_at DESC`
+      );
+      res.render('postfach', {
+        emails,
+        bewerbungen,
+        mailConfigured: mailer.isConfigured(),
+        mailError: req.query.mailerror ? String(req.query.mailerror) : '',
+        mailOk: req.query.mailok ? String(req.query.mailok) : '',
+        hideSettings: true,
+      });
+    } catch (error) {
+      console.error('Error loading postfach:', error);
+      res.status(500).send('Serverfehler');
+    }
+  });
+
+  // Assign an unlinked e-mail to an existing application.
+  app.post('/postfach/:emailId/zuweisen', async (req, res) => {
+    try {
+      const bewerbungId = Number(req.body.bewerbung_id);
+      if (!bewerbungId) {
+        return res.redirect('/postfach?mailerror=' + encodeURIComponent('Bitte eine Bewerbung auswählen.'));
+      }
+      // Make sure the target application exists and the e-mail is still unlinked.
+      const app = await dbGet('SELECT id FROM bewerbungen WHERE id = ?', [bewerbungId]);
+      if (!app) {
+        return res.redirect('/postfach?mailerror=' + encodeURIComponent('Ausgewählte Bewerbung existiert nicht.'));
+      }
+      await dbRun('UPDATE emails SET bewerbung_id = ? WHERE id = ? AND bewerbung_id IS NULL', [bewerbungId, req.params.emailId]);
+      res.redirect('/postfach?mailok=' + encodeURIComponent('E-Mail wurde der Bewerbung zugewiesen.'));
+    } catch (error) {
+      console.error('Error assigning e-mail:', error);
+      res.redirect('/postfach?mailerror=' + encodeURIComponent('Zuweisung fehlgeschlagen: ' + (error.message || 'Unbekannter Fehler')));
+    }
+  });
+
+  // Count of unlinked e-mails — drives the header badge on every page.
+  app.get('/api/emails/unassigned-count', async (req, res) => {
+    try {
+      const row = await dbGet('SELECT COUNT(*) as count FROM emails WHERE bewerbung_id IS NULL');
+      res.json({ count: row ? row.count : 0 });
+    } catch (error) {
+      res.status(500).json({ count: 0 });
+    }
+  });
+
   // Add a timeline entry (status change with date + comment)
   app.post('/bewerbung/:id/verlauf', async (req, res) => {
     try {