feat: enhance tenant admin experience with form locking and column visibility settings

adminfront/src/features/users/UserCreatePage.tsx

@@ -50,10 +50,16 @@ function UserCreatePage() {
   });
   const tenants = tenantsData?.items ?? [];
 
+  const { data: profile } = useQuery({
+    queryKey: ["me"],
+    queryFn: fetchMe,
+  });
+
   const {
     register,
     handleSubmit,
     watch,
+    setValue,
     formState: { errors },
   } = useForm<UserFormValues>({
     defaultValues: {
@@ -70,6 +76,13 @@ function UserCreatePage() {
     },
   });
 
+  // Lock company for tenant_admin
+  React.useEffect(() => {
+    if (profile?.role === "tenant_admin" && profile.companyCode) {
+      setValue("companyCode", profile.companyCode);
+    }
+  }, [profile, setValue]);
+
   const selectedCompanyCode = watch("companyCode");
   const selectedTenant = tenants.find((t) => t.slug === selectedCompanyCode);
 
@@ -352,6 +365,7 @@ function UserCreatePage() {
                     id="companyCode"
                     className="flex h-9 w-full rounded-md border border-input bg-transparent px-3 py-1 text-sm shadow-sm transition-colors file:border-0 file:bg-transparent file:text-sm file:font-medium placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-1 focus-visible:ring-ring disabled:cursor-not-allowed disabled:opacity-50"
                     {...register("companyCode")}
+                    disabled={profile?.role === "tenant_admin"}
                   >
                     <option value="">
                       {t(