fix(chat): repair Arco migration fallout in the chat page

The Phase 006 walkthrough surfaced four issues the automated checks could
not see. Dead naive-ui class names left behind by the migration stopped
matching, tooltips that carried their label as trailing default-slot text
leaked that text into the flex row, the workspace panel squeezed the chat
column until the input toolbar wrapped, and the Escape fallback still
looked for naive-ui's modal mask.

Tooltips now pass their label through the content prop, the tool panel
reserves a minimum width for the chat column, and Escape finds the visible
Arco modal and clicks its close button.

packages/client/src/components/hermes/chat/ChatPanel.vue

@@ -44,6 +44,9 @@ const activeWorkspaceSessionId = computed(() => chatStore.activeSession?.workspa
 const activeWorkspacePath = computed(() => chatStore.activeSession?.workspace && !chatStore.activeSession.isLocalOnly ? chatStore.activeSession.workspace : null);
 const TOOL_PANEL_MIN_WIDTH = 360;
 const TOOL_PANEL_DEFAULT_WIDTH = 560;
+// 工具栏要单行放下：附件 + 推理强度 + 设置 + 模型下拉（最长 190px）+ 语音 + 发送，
+// 再加输入框左右内边距。窄于此值 Arco 按钮会被挤成竖排。
+const CHAT_MAIN_MIN_WIDTH = 620;
 const TOOL_PANEL_STORAGE_KEY = "hermes.chat.toolPanelWidth";
 const toolPanelWidth = ref(loadToolPanelWidth());
 const toolResizeStart = ref<{ x: number; width: number } | null>(null);
@@ -102,7 +105,9 @@ function toolPanelMaxWidth() {
   if (typeof window === "undefined") return 1180;
   if (isMobile.value) return window.innerWidth;
   const available = chatContentWrapperRef.value?.clientWidth || window.innerWidth;
-  return Math.max(320, Math.min(Math.floor(available * 0.88), available - 120));
+  // 主区要放得下输入工具栏（附件 + 推理强度 + 设置 + 模型 + 语音 + 发送），
+  // 否则面板一展开工具栏就被压成竖排。
+  return Math.max(320, Math.min(Math.floor(available * 0.88), available - CHAT_MAIN_MIN_WIDTH));
 }
 
 function clampToolPanelWidth(width: number) {
@@ -2068,7 +2073,7 @@ async function handleSessionModelCustomSubmit() {
   gap: 4px;
   height: 22px;
 
-  .n-button {
+  .arco-btn {
     display: inline-flex;
     align-items: center;
     justify-content: center;
@@ -2150,24 +2155,20 @@ async function handleSessionModelCustomSubmit() {
   gap: 14px;
 }
 
-:deep(.new-chat-drawer .n-drawer-content) {
+:deep(.new-chat-drawer .arco-drawer) {
   height: 100%;
   display: flex;
   flex-direction: column;
 }
 
-:deep(.new-chat-drawer .n-drawer-header),
-:deep(.new-chat-drawer .n-drawer-footer) {
+:deep(.new-chat-drawer .arco-drawer-header),
+:deep(.new-chat-drawer .arco-drawer-footer) {
   flex-shrink: 0;
 }
 
-:deep(.new-chat-drawer .n-drawer-body) {
+:deep(.new-chat-drawer .arco-drawer-body) {
   flex: 1 1 auto;
   min-height: 0;
-  overflow: hidden;
-}
-
-:deep(.new-chat-drawer .n-drawer-body-content-wrapper) {
   height: 100%;
   overflow-y: auto;
 }
@@ -2181,7 +2182,7 @@ async function handleSessionModelCustomSubmit() {
 }
 
 @media (max-width: $breakpoint-mobile) {
-  :deep(.new-chat-drawer .n-drawer-body-content-wrapper) {
+  :deep(.new-chat-drawer .arco-drawer-body) {
     padding-top: 12px;
     padding-bottom: 12px;
   }