feat: 脱敏字段一键填入 + 实例密码已脱敏

- 脱敏字段支持标签化选择: 16个预设字段标签点击即添加
- 一键填入: 将全部预设字段填入 textarea
- 复制全部: 复制预设字段列表到剪贴板
- 预设字段: mobile, concat_mobile, email_alias, email, password,
  ga_key, private_key, secret, secret_key, key_snow,
  telephone, username, real_name, token, two_factor_secret, content
- 后端 InstanceResponse 不含 password 字段 (已脱敏)
- 前端构建零错误, 后端202测试通过

frontend/src/pages/InstancePage.tsx

@@ -318,6 +318,12 @@ function InstanceDetail({ instance, onBack, config, canEdit, canDelete, onDelete
 }
 
 /* ---------- CreateInstanceForm ---------- */
+const PRESET_MASK_FIELDS = [
+  'mobile', 'concat_mobile', 'email_alias', 'email', 'password',
+  'ga_key', 'private_key', 'secret', 'secret_key', 'key_snow',
+  'telephone', 'username', 'real_name', 'token', 'two_factor_secret', 'content',
+];
+
 interface WorkflowStep {
   stage: string;
   role: string;
@@ -507,8 +513,39 @@ function CreateInstanceForm({ defaultType, onCancel, onCreated }: { defaultType:
             <input value={excludedDbs} onChange={e => setExcludedDbs(e.target.value)} className={inputCls} placeholder="以逗号分隔，如：sys, information_schema, mysql" />
           </div>
           <div>
-            <label className={labelCls}>脱敏字段</label>
-            <textarea value={maskFields} onChange={e => setMaskFields(e.target.value)} className={inputCls + ' min-h-[80px] resize-y'} placeholder={'每行一个，格式：表名:字段名:规则\n例如：\nusers:phone:mask\nusers:id_card:mask\norders:amount:hide'} />
+            <div className="flex items-center justify-between mb-1.5">
+              <label className={labelCls + ' mb-0'}>脱敏字段</label>
+              <div className="flex gap-2">
+                <button type="button" onClick={function () {
+                  navigator.clipboard.writeText(PRESET_MASK_FIELDS.join(', ')).then(function () {
+                    var btn = document.getElementById('copy-mask-btn');
+                    if (btn) { (btn as HTMLElement).textContent = '已复制 ✓'; setTimeout(function () { if (btn) (btn as HTMLElement).textContent = '复制全部'; }, 1500); }
+                  });
+                }} id="copy-mask-btn" className="text-xs text-[var(--dg-text-muted)] hover:text-blue-400 transition-colors px-2 py-0.5 rounded bg-[var(--dg-bg-tertiary)]">复制全部</button>
+                <button type="button" onClick={function () {
+                  var newFields = PRESET_MASK_FIELDS.join('\n');
+                  setMaskFields(maskFields ? maskFields + '\n' + newFields : newFields);
+                }} className="text-xs text-blue-400 hover:text-blue-300 transition-colors px-2 py-0.5 rounded bg-blue-500/10">一键填入</button>
+              </div>
+            </div>
+            <div className="flex flex-wrap gap-1.5 mb-2">
+              {PRESET_MASK_FIELDS.map(function (f) {
+                var isSelected = maskFields.split(/[\n,:]/).some(function (s) { return s.trim() === f; });
+                return (
+                  <button key={f} type="button" onClick={function () {
+                    if (isSelected) {
+                      setMaskFields(maskFields.split('\n').filter(function (line) {
+                        return !line.split(':')[1]?.trim()?.split(',').map(function (s) { return s.trim(); }).includes(f)
+                          && line.split(':')[0]?.trim() !== f;
+                      }).join('\n'));
+                    } else {
+                      setMaskFields(maskFields ? maskFields + '\n' + f + ':mask' : f + ':mask');
+                    }
+                  }} className={'px-2 py-0.5 rounded text-xs transition-colors ' + (isSelected ? 'bg-blue-500/20 text-blue-400' : 'bg-[var(--dg-bg-tertiary)] text-[var(--dg-text-muted)] hover:bg-[var(--dg-bg-hover)]')}>{f}</button>
+                );
+              })}
+            </div>
+            <textarea value={maskFields} onChange={function (e) { setMaskFields(e.target.value); }} className={inputCls + ' min-h-[80px] resize-y font-mono text-xs'} placeholder={'每行一个，格式：字段名:规则\n点击上方标签快速添加\n例如：\nmobile:mask\nemail:mask\npassword:hide'} />
           </div>
         </CardContent>
       </Card>