fix: 移除所有弹框遮罩层点击关闭 — 防止输入时误触关闭

涉及文件 (12处):
- InstancePage.tsx: 添加数据源弹框
- UsersPage.tsx: 新建/编辑/重置密码/详情弹框 (4处)
- RolesPage.tsx: 克隆角色弹框
- InstanceGroupPage.tsx: 新建/编辑/关联实例/关联用户弹框 (4处)
- SlowQueryPage.tsx: 查询对比弹框
- RedisDetailPage.tsx: 键详情/新增键弹框 (2处)

改动: 遮罩层div移除onClick，只能通过X按钮或取消按钮关闭

frontend/src/pages/InstanceGroupPage.tsx

@@ -703,7 +703,7 @@ export default function InstanceGroupPage() {
 
       {/* Create Modal */}
       {showCreateModal && (
-        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50" onClick={() => { setShowCreateModal(false); resetForm(); }}>
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
           <div className="w-full max-w-lg bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-2xl" onClick={e => e.stopPropagation()}>
             <h3 className="text-lg font-semibold mb-4">新建权限组</h3>
             {renderGroupForm(handleCreate, '创建')}
@@ -713,7 +713,7 @@ export default function InstanceGroupPage() {
 
       {/* Edit Modal */}
       {showEditModal && (
-        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50" onClick={() => { setShowEditModal(false); resetForm(); }}>
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
           <div className="w-full max-w-lg bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-2xl" onClick={e => e.stopPropagation()}>
             <h3 className="text-lg font-semibold mb-4">编辑权限组</h3>
             {renderGroupForm(handleEdit, '保存')}
@@ -723,7 +723,7 @@ export default function InstanceGroupPage() {
 
       {/* Instance Modal with search */}
       {showInstanceModal && (
-        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50" onClick={() => setShowInstanceModal(false)}>
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
           <div className="w-full max-w-md bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-2xl" onClick={e => e.stopPropagation()}>
             <h3 className="text-lg font-semibold mb-4">关联实例</h3>
             <div className="relative mb-3">
@@ -758,7 +758,7 @@ export default function InstanceGroupPage() {
 
       {/* User Modal with search */}
       {showUserModal && (
-        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50" onClick={() => setShowUserModal(false)}>
+        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50">
           <div className="w-full max-w-md bg-[var(--dg-bg-primary)] border border-[var(--dg-border)] rounded-xl p-6 shadow-2xl" onClick={e => e.stopPropagation()}>
             <h3 className="text-lg font-semibold mb-4">关联用户</h3>
             <div className="relative mb-3">