统一PC前端布局密度（05-28-pc-frontend-layout-unification）

client/src/pages/MasterDataPage.tsx

@@ -341,7 +341,7 @@ export function MasterDataPage() {
           <TabsTrigger value="suppliers">供应商</TabsTrigger>
         </TabsList>
 
-        <TabsContent value="legal-entities" className="space-y-6">
+        <TabsContent value="legal-entities" className="space-y-4">
           <FilterBar className="ops-command-bar !p-3 md:!p-3.5">
             <div className="flex flex-wrap items-center justify-between gap-3">
               <h3 className="text-base font-semibold text-zinc-900">法体筛选</h3>
@@ -454,7 +454,7 @@ export function MasterDataPage() {
           </div>
         </TabsContent>
 
-        <TabsContent value="cost-centers" className="space-y-6">
+        <TabsContent value="cost-centers" className="space-y-4">
           <FilterBar className="ops-command-bar !p-3 md:!p-3.5">
             <div className="grid gap-3 md:grid-cols-3">
               <select
@@ -613,7 +613,7 @@ export function MasterDataPage() {
           </div>
         </TabsContent>
 
-        <TabsContent value="document-categories" className="space-y-6">
+        <TabsContent value="document-categories" className="space-y-4">
           <FilterBar className="ops-command-bar !p-3 md:!p-3.5">
             <div className="grid gap-3 md:grid-cols-3">
               <select
@@ -780,14 +780,14 @@ export function MasterDataPage() {
           </div>
         </TabsContent>
 
-        <TabsContent value="holiday-calendars" className="space-y-6">
+        <TabsContent value="holiday-calendars" className="space-y-4">
           <HolidayCalendarTab
             canManage={canManage}
             includeArchived={includeArchived}
             legalEntities={legalEntities}
           />
         </TabsContent>
-        <TabsContent value="suppliers" className="space-y-6">
+        <TabsContent value="suppliers" className="space-y-4">
           <SupplierTab
             canManage={canManage}
             includeArchived={includeArchived}