feat(ios): refine native ui controls

apps/ios/Sources/MultiSimAdmin/Features/Fleet/InstanceFormView.swift

@@ -9,6 +9,11 @@ struct InstanceFormView: View {
     @State private var password = ""
     @State private var validationMessage: String?
 
+    private var canSave: Bool {
+        !name.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
+            && !originText.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
+    }
+
     var body: some View {
         NavigationStack {
             ZStack {
@@ -20,19 +25,15 @@ struct InstanceFormView: View {
                                 field("名称", text: $name, placeholder: "Home Node")
                                 field("地址", text: $originText, placeholder: "http://192.168.1.10:3000")
                                 field("标签", text: $tagsText, placeholder: "home, primary")
-                                SecureField("实例密码（可选）", text: $password)
-                                    .textContentType(.password)
-                                    .padding(.horizontal, 12)
-                                    .frame(minHeight: 38)
-                                    .background(AITheme.canvas)
-                                    .clipShape(RoundedRectangle(cornerRadius: AITheme.buttonRadius))
+                                field("实例密码", text: $password, placeholder: "可选，保存到钥匙串", secure: true)
                             }
                         }
                         if let validationMessage {
-                            Text(validationMessage)
-                                .font(.subheadline)
-                                .foregroundStyle(AITheme.danger)
-                                .frame(maxWidth: .infinity, alignment: .leading)
+                            AICard {
+                                Label(validationMessage, systemImage: "exclamationmark.triangle")
+                                    .font(.subheadline)
+                                    .foregroundStyle(AITheme.danger)
+                            }
                         }
                     }
                     .padding(16)
@@ -49,26 +50,35 @@ struct InstanceFormView: View {
                         save()
                     }
                     .buttonStyle(AIButtonStyle(kind: .primary, size: .regular))
+                    .disabled(!canSave)
                 }
             }
         }
     }
 
-    private func field(_ title: String, text: Binding<String>, placeholder: String) -> some View {
+    private func field(
+        _ title: String,
+        text: Binding<String>,
+        placeholder: String,
+        secure: Bool = false
+    ) -> some View {
         VStack(alignment: .leading, spacing: 6) {
             Text(title)
                 .font(.subheadline.weight(.semibold))
                 .foregroundStyle(AITheme.ink)
-            TextField(placeholder, text: text)
-                .textFieldStyle(.plain)
-                .padding(.horizontal, 12)
-                .frame(minHeight: 38)
-                .background(AITheme.canvas)
-                .clipShape(RoundedRectangle(cornerRadius: AITheme.buttonRadius))
+            if secure {
+                SecureField(placeholder, text: text)
+                    .textFieldStyle(AIFieldStyle())
+                    .textContentType(.password)
+            } else {
+                TextField(placeholder, text: text)
+                    .textFieldStyle(AIFieldStyle())
+            }
         }
     }
 
     private func save() {
+        let normalizedName = name.trimmingCharacters(in: .whitespacesAndNewlines)
         guard let origin = URL(string: originText.trimmingCharacters(in: .whitespacesAndNewlines)),
               origin.scheme == "http" || origin.scheme == "https",
               origin.host != nil
@@ -81,7 +91,7 @@ struct InstanceFormView: View {
             .map { $0.trimmingCharacters(in: .whitespacesAndNewlines) }
             .filter { !$0.isEmpty }
         let input = InstanceInput(
-            name: name,
+            name: normalizedName,
             origin: origin,
             tags: tags,
             password: password.isEmpty ? nil : password