fix: 修复 QA 巡检发现的 console 告警——useForm 未连接、RangePicker 空值禁用、dashboard 占用率类型

apps/admin/src/pages/ClassroomRentals/index.tsx

@@ -507,6 +507,7 @@ const ClassroomRentalsPage: React.FC = () => {
               style={{ width: '100%' }}
               placeholder={['开始日期', '结束日期']}
               format="YYYY-MM-DD"
+              allowEmpty={[true, true]}
               disabled={!selectedClassroomId}
               disabledDate={(date) => unavailableDatesLoading || isDateUnavailable(date)}
               onPanelChange={(dates) => dates.forEach((date) => date && handleCalendarChange(date))}

apps/admin/src/pages/Roles/index.tsx

@@ -352,7 +352,7 @@ const RolesPage: React.FC = () => {
         onOk={handleSubmit}
         onCancel={() => roleGuard.confirmClose(() => setModalOpen(false))}
         width={700}
-        destroyOnHidden
+        forceRender
         confirmLoading={saving}
       >
         <Form form={form} layout="vertical">

apps/admin/src/pages/Users/index.tsx

@@ -449,7 +449,7 @@ const UsersPage: React.FC = () => {
         open={modalOpen}
         onOk={handleSubmit}
         onCancel={() => accountGuard.confirmClose(() => setModalOpen(false))}
-        destroyOnHidden
+        forceRender
         confirmLoading={saving}
       >
         <Form form={form} layout="vertical">
@@ -496,7 +496,7 @@ const UsersPage: React.FC = () => {
         open={pwdModalOpen}
         onOk={handlePwdSubmit}
         onCancel={() => pwdGuard.confirmClose(() => setPwdModalOpen(false))}
-        destroyOnHidden
+        forceRender
         confirmLoading={saving}
       >
         <Form form={pwdForm} layout="vertical">
@@ -515,7 +515,7 @@ const UsersPage: React.FC = () => {
         open={profileModalOpen}
         onOk={handleProfileSubmit}
         onCancel={() => profileGuard.confirmClose(() => setProfileModalOpen(false))}
-        destroyOnHidden
+        forceRender
         confirmLoading={saving}
       >
         <Form form={profileForm} layout="vertical">

apps/server/src/dashboard/dashboard.service.ts

@@ -103,7 +103,7 @@ export class DashboardService {
     const totalCapacity = await capQb.getRawOne<{ total: string | number | null }>();
     // MySQL 的 SUM() 聚合默认以字符串返回，需显式转成 number
     const cap = Number(totalCapacity?.total ?? 0) || 0;
-    const occupancyRate = cap > 0 ? ((occupiedBeds / cap) * 100).toFixed(1) : 0;
+    const occupancyRate = cap > 0 ? ((occupiedBeds / cap) * 100).toFixed(1) : '0.0';
 
     const billStatsQb = this.billRepo
       .createQueryBuilder('b')