新增清潔費欄位 {{清潔費}}，並記憶每份範本上次使用的值

- 表單新增「清潔費」欄位，預設 1200
- 後端 PDF 產生成功後自動將 monthlyRent / paymentDay / deposit / cleaningFee
  寫入 templates/defaults.json，key 為範本檔名
- 切換範本時呼叫 /api/templates/:name/defaults 自動帶入上次的值
- 表單版面調整為 2x2：每月租金/繳款日期、保證金/清潔費 各一行
- 4 份逢甲範本加入 {{清潔費}} 佔位符

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

public/app.js

@@ -23,7 +23,10 @@ document.getElementById('leaseStart').addEventListener('change', (e) => {
   schedulePreview();
 });
 
-templateSelect.addEventListener('change', () => loadPreview());
+templateSelect.addEventListener('change', () => {
+  loadTemplateDefaults(templateSelect.value);
+  loadPreview();
+});
 
 let previewTimer = null;
 function schedulePreview() {
@@ -50,6 +53,7 @@ form.addEventListener('submit', async (event) => {
         monthlyRent: formData.get('monthlyRent'),
         paymentDay: formData.get('paymentDay'),
         deposit: formData.get('deposit'),
+        cleaningFee: formData.get('cleaningFee'),
         leaseStart: formData.get('leaseStart'),
         leaseEnd: formData.get('leaseEnd'),
       }),
@@ -119,6 +123,7 @@ async function loadTemplates() {
     }
 
     connectionStatus.textContent = '可使用';
+    loadTemplateDefaults(templateSelect.value);
     loadPreview();
   } catch (error) {
     templateSelect.append(new Option('讀取失敗', ''));
@@ -129,6 +134,19 @@ async function loadTemplates() {
   }
 }
 
+async function loadTemplateDefaults(name) {
+  if (!name) return;
+  try {
+    const res = await fetch(`/api/templates/${encodeURIComponent(name)}/defaults`);
+    if (!res.ok) return;
+    const defaults = await res.json();
+    if (defaults.monthlyRent) form.elements.monthlyRent.value = defaults.monthlyRent;
+    if (defaults.paymentDay)  form.elements.paymentDay.value  = defaults.paymentDay;
+    if (defaults.deposit)     form.elements.deposit.value     = defaults.deposit;
+    if (defaults.cleaningFee) form.elements.cleaningFee.value = defaults.cleaningFee;
+  } catch {}
+}
+
 let previewGen = 0;
 let previewAbortController = null;
 let previewBlobUrl = null;
@@ -151,6 +169,7 @@ async function loadPreview() {
     monthlyRent: formData.get('monthlyRent') || '',
     paymentDay:  formData.get('paymentDay')  || '',
     deposit:     formData.get('deposit')     || '',
+    cleaningFee: formData.get('cleaningFee') || '',
     leaseStart:  formData.get('leaseStart')  || '',
     leaseEnd:    formData.get('leaseEnd')    || '',
   });

public/index.html

@@ -50,7 +50,7 @@
             </div>
 
             <div class="tool-panel fields-panel">
-              <div class="field-grid">
+              <div class="field-grid field-grid--2">
                 <label class="field">
                   <span>每月租金</span>
                   <input name="monthlyRent" type="number" inputmode="numeric" min="1" step="1" value="8000" required>
@@ -63,6 +63,10 @@
                   <span>保證金</span>
                   <input name="deposit" type="number" inputmode="numeric" min="1" step="1" value="16000" required>
                 </label>
+                <label class="field">
+                  <span>清潔費</span>
+                  <input name="cleaningFee" type="number" inputmode="numeric" min="1" step="1" value="1200" required>
+                </label>
               </div>
 
               <div class="field-grid field-grid--2">