feat(domain): improve domain form UX

- Make name field optional (defaults to domain if empty)
- Simplify domain placeholder and error messages
- Add test connection button for credential validation before save

src/main/ipc-handlers.ts

@@ -24,6 +24,7 @@ import type { Result } from "@renderer/types/ipc";
 import type {
   CreateDomainParams,
   UpdateDomainParams,
+  TestDomainConnectionParams,
   GetSpacesParams,
   GetAppsParams,
   GetAppDetailParams,
@@ -206,6 +207,37 @@ function registerTestConnection(): void {
   });
 }
 
+/**
+ * Test domain connection with temporary credentials
+ */
+function registerTestDomainConnection(): void {
+  handleWithParams<TestDomainConnectionParams, boolean>(
+    "testDomainConnection",
+    async (params) => {
+      const tempDomain: DomainWithPassword = {
+        id: "temp",
+        name: "temp",
+        domain: params.domain,
+        username: params.username,
+        password: params.password || "",
+        authType: params.authType,
+        apiToken: params.apiToken,
+        createdAt: new Date().toISOString(),
+        updatedAt: new Date().toISOString(),
+      };
+
+      const client = new KintoneClient(tempDomain);
+      const result = await client.testConnection();
+
+      if (!result.success) {
+        throw new Error(result.error || "Connection failed");
+      }
+
+      return true;
+    },
+  );
+}
+
 // ==================== Browse IPC Handlers ====================
 
 /**
@@ -521,6 +553,7 @@ export function registerIpcHandlers(): void {
   registerUpdateDomain();
   registerDeleteDomain();
   registerTestConnection();
+  registerTestDomainConnection();
 
   // Browse
   registerGetSpaces();