feat(ios): unify list cards and loading states

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

@@ -14,23 +14,22 @@ struct FleetView: View {
             ScrollView {
                 LazyVStack(spacing: 12) {
                     searchField
+                    if let errorMessage = model.errorMessage {
+                        AIStatusBanner(errorMessage, tint: AITheme.danger, systemImage: "exclamationmark.triangle")
+                    }
                     if model.selectionMode {
                         selectionBar
                     }
+                    if model.isLoading && model.rows.isEmpty {
+                        AILoadingCard("正在同步实例")
+                    }
                     if model.rows.isEmpty && !model.isLoading {
                         AICard {
-                            VStack(spacing: 10) {
-                                Image(systemName: "server.rack")
-                                    .font(.system(size: 28))
-                                    .foregroundStyle(AITheme.muted)
-                                Text("暂无实例")
-                                    .font(.headline)
-                                Text("添加 SimAdmin 实例后即可开始管理。")
-                                    .font(.subheadline)
-                                    .foregroundStyle(AITheme.muted)
-                            }
-                            .frame(maxWidth: .infinity)
-                            .padding(.vertical, 18)
+                            AIEmptyState(
+                                systemImage: "server.rack",
+                                title: "暂无实例",
+                                message: "添加 SimAdmin 实例后即可开始管理。"
+                            )
                         }
                     }
                     ForEach(model.rows) { row in
@@ -50,22 +49,23 @@ struct FleetView: View {
             }
         }
         .navigationTitle("节点总览")
-        .toolbar {
-            ToolbarItemGroup(placement: .primaryAction) {
-                Button {
-                    model.selectionMode.toggle()
-                    model.selectedIDs.removeAll()
-                } label: {
-                    Label(model.selectionMode ? "完成" : "批量选择", systemImage: model.selectionMode ? "xmark" : "checklist")
-                }
-                .buttonStyle(AIButtonStyle(kind: .secondary, size: .regular))
+        .aiBottomActionBar {
+            if !model.selectionMode {
+                HStack(spacing: 10) {
+                    Button {
+                        model.selectionMode = true
+                    } label: {
+                        Label("批量选择", systemImage: "checklist")
+                    }
+                    .buttonStyle(AIButtonStyle(kind: .secondary, size: .regular, fillsWidth: true))
 
-                Button {
-                    model.showingForm = true
-                } label: {
-                    Label("添加实例", systemImage: "plus")
+                    Button {
+                        model.showingForm = true
+                    } label: {
+                        Label("添加实例", systemImage: "plus")
+                    }
+                    .buttonStyle(AIButtonStyle(kind: .primary, size: .regular, fillsWidth: true))
                 }
-                .buttonStyle(AIButtonStyle(kind: .primary, size: .regular))
             }
         }
         .confirmationDialog(
@@ -110,7 +110,13 @@ struct FleetView: View {
                         systemImage: "checkmark.circle"
                     )
                 }
-                .buttonStyle(AIButtonStyle(kind: .secondary, size: .compact))
+                .buttonStyle(
+                    AIButtonStyle(
+                        kind: .secondary,
+                        size: .compact,
+                        fixedWidth: AITheme.footerSecondaryButtonWidth
+                    )
+                )
 
                 Spacer()
 
@@ -123,7 +129,13 @@ struct FleetView: View {
                 } label: {
                     Label("删除", systemImage: "trash")
                 }
-                .buttonStyle(AIButtonStyle(kind: .danger, size: .compact))
+                .buttonStyle(
+                    AIButtonStyle(
+                        kind: .danger,
+                        size: .compact,
+                        fixedWidth: AITheme.footerSecondaryButtonWidth
+                    )
+                )
                 .disabled(model.selectedIDs.isEmpty)
             }
         }
@@ -143,6 +155,8 @@ struct FleetView: View {
                     }
                     .buttonStyle(.plain)
                     .frame(width: 32, height: 32)
+                    .accessibilityLabel(model.selectedIDs.contains(row.id) ? "取消选择" : "选择")
+                    .accessibilityAddTraits(model.selectedIDs.contains(row.id) ? .isSelected : [])
                 }
                 VStack(alignment: .leading, spacing: 8) {
                     HStack(spacing: 8) {
@@ -155,6 +169,8 @@ struct FleetView: View {
                     Text(row.instance.origin.absoluteString)
                         .font(.subheadline)
                         .foregroundStyle(AITheme.muted)
+                        .lineLimit(1)
+                        .truncationMode(.middle)
                     if !row.instance.tags.isEmpty {
                         HStack(spacing: 6) {
                             ForEach(row.instance.tags, id: \.self) { tag in