Fix monthly PDF export to include only the selected month

The month dropdown carried only the month (e.g. "07") while the year was
a separate select; the export required month AND year, so a month-only
selection fell through to exporting every application. Encode the year in
the month option value ("YYYY-MM"), parse it client-side to always send
the exact month+year, and harden /api/export so a month can never fall
through to "export all".

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

public/js/main.js

@@ -251,9 +251,21 @@ function openPdfExportModal() {
 function generatePDF(event) {
     event.preventDefault();
     
-    const month = document.getElementById('pdfMonth').value;
-    const year = document.getElementById('pdfYear').value;
-    
+    // The month option encodes its year ("YYYY-MM"), so a chosen month always
+    // exports exactly that month of that year, regardless of the year select.
+    const monthRaw = document.getElementById('pdfMonth').value;
+    let year = document.getElementById('pdfYear').value;
+    let month = '';
+    if (monthRaw) {
+        if (monthRaw.indexOf('-') !== -1) {
+            const parts = monthRaw.split('-');
+            year = parts[0];
+            month = parts[1];
+        } else {
+            month = monthRaw;
+        }
+    }
+
     // Fetch data for PDF
     let url = '/api/export?';
     const params = [];

server.js

@@ -849,6 +849,11 @@ initializeDatabase().then(() => {
       if (month && year) {
         query = 'SELECT * FROM bewerbungen WHERE strftime("%m", datum) = ? AND strftime("%Y", datum) = ? ORDER BY datum DESC';
         params.push(month.padStart(2, '0'), year);
+      } else if (month) {
+        // A month without a year must still restrict the export to that month —
+        // never fall through to exporting every application.
+        query = 'SELECT * FROM bewerbungen WHERE strftime("%m", datum) = ? ORDER BY datum DESC';
+        params.push(month.padStart(2, '0'));
       } else if (year) {
         query = 'SELECT * FROM bewerbungen WHERE strftime("%Y", datum) = ? ORDER BY datum DESC';
         params.push(year);

views/index.ejs

@@ -568,11 +568,11 @@
                             class="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-md bg-white dark:bg-gray-700 text-gray-800 dark:text-white">
                             <option value="">-- Alle Monate --</option>
                             <% availableMonths.forEach(m => { %>
-                                <option value="<%= m.month %>"><%= m.month %> - <%= m.year %></option>
+                                <option value="<%= m.year %>-<%= m.month %>"><%= m.month %> - <%= m.year %></option>
                             <% }); %>
                         </select>
                     </div>
-                    
+
                     <div>
                         <label for="pdfYear" class="block text-sm font-medium text-gray-700 dark:text-gray-300 mb-2">
                             Jahr