i18n(SubAgentPage): complete internationalization for subagent orchestration page (#5400)

* i18n: complete internationalization for subagent orchestration page

- Replace hardcoded English strings in [SubAgentPage.vue] with i18n keys.
- Update `en-US` and `zh-CN` locales with missing hints, validation messages, and empty state translations.
- Fix translation typos and improve consistency across the SubAgent orchestration UI.

* fix(bug_risk): 避免在模板中的翻译调用上使用 || 'Close' 作为回退值。

dashboard/src/i18n/locales/en-US/features/subagent.json

@@ -8,11 +8,14 @@
     "refresh": "Refresh",
     "save": "Save",
     "add": "Add SubAgent",
-    "delete": "Delete"
+    "delete": "Delete",
+    "close": "Close"
   },
   "switches": {
     "enable": "Enable SubAgent orchestration",
-    "dedupe": "Deduplicate main LLM tools (hide tools duplicated by SubAgents)"
+    "enableHint": "Enable sub-agent functionality",
+    "dedupe": "Deduplicate main LLM tools (hide tools duplicated by SubAgents)",
+    "dedupeHint": "Remove duplicate tools from main agent"
   },
   "description": {
     "disabled": "When off: SubAgent is disabled; the main LLM mounts tools via persona rules (all by default) and calls them directly.",
@@ -29,7 +32,8 @@
     "transferPrefix": "transfer_to_{name}",
     "switchLabel": "Enable",
     "previewTitle": "Preview: handoff tool shown to the main LLM",
-    "personaChip": "Persona: {id}"
+    "personaChip": "Persona: {id}",
+    "personaPreview": "PERSONA PREVIEW"
   },
   "form": {
     "nameLabel": "Agent name (used for transfer_to_{name})",
@@ -49,6 +53,13 @@
     "nameDuplicate": "Duplicate SubAgent name: {name}",
     "personaMissing": "SubAgent {name} has no persona selected",
     "saveSuccess": "Saved successfully",
-    "saveFailed": "Failed to save"
+    "saveFailed": "Failed to save",
+    "nameRequired": "Name is required",
+    "namePattern": "Lowercase letters, numbers, underscore only"
+  },
+  "empty": {
+    "title": "No Agents Configured",
+    "subtitle": "Add a new sub-agent to get started",
+    "action": "Create First Agent"
   }
 }

dashboard/src/i18n/locales/zh-CN/features/subagent.json

@@ -8,11 +8,14 @@
     "refresh": "刷新",
     "save": "保存",
     "add": "新增 SubAgent",
-    "delete": "删除"
+    "delete": "删除",
+    "close": "关闭"
   },
   "switches": {
     "enable": "启用 SubAgent 编排",
-    "dedupe": "主 LLM 去重重复工具（与 SubAgent 重叠的工具将被隐藏）"
+    "enableHint": "启用子代理功能",
+    "dedupe": "主 LLM 去重重复工具（与 SubAgent 重叠的工具将被隐藏）",
+    "dedupeHint": "从主代理中移除重复工具"
   },
   "description": {
     "disabled": "不启动：SubAgent 关闭；主 LLM 按 persona 规则挂载工具（默认全部），并直接调用。",
@@ -39,6 +42,7 @@
     "providerHint": "留空表示跟随全局默认 provider。",
     "personaLabel": "选择人格设定",
     "personaHint": "SubAgent 将直接继承所选 Persona 的系统设定与工具。在人格设定页管理和新建人格。",
+    "personaPreview": "人格预览",
     "descriptionLabel": "对主 LLM 的描述（用于决定是否 handoff）",
     "descriptionHint": "这段会作为 transfer_to_* 工具的描述给主 LLM 看，建议简短明确。"
   },
@@ -50,6 +54,13 @@
     "nameDuplicate": "SubAgent 名称重复：{name}",
     "personaMissing": "SubAgent {name} 未选择 Persona",
     "saveSuccess": "保存成功",
-    "saveFailed": "保存失败"
+    "saveFailed": "保存失败",
+    "nameRequired": "名称必填",
+    "namePattern": "仅支持小写字母、数字和下划线"
+  },
+  "empty": {
+    "title": "未配置 SubAgent",
+    "subtitle": "添加一个新的子代理以开始",
+    "action": "创建第一个 Agent"
   }
 }

dashboard/src/views/SubAgentPage.vue

@@ -62,7 +62,7 @@
               <template #label>
                 <div class="d-flex flex-column">
                   <span class="text-body-2 font-weight-medium">{{ tm('switches.enable') }}</span>
-                  <span class="text-caption text-medium-emphasis">Enable sub-agent functionality</span>
+                  <span class="text-caption text-medium-emphasis">{{ tm('switches.enableHint') }}</span>
                 </div>
               </template>
             </v-switch>
@@ -80,7 +80,7 @@
               <template #label>
                 <div class="d-flex flex-column">
                   <span class="text-body-2 font-weight-medium">{{ tm('switches.dedupe') }}</span>
-                  <span class="text-caption text-medium-emphasis">Remove duplicate tools from main agent</span>
+                  <span class="text-caption text-medium-emphasis">{{ tm('switches.dedupeHint') }}</span>
                 </div>
               </template>
             </v-switch>
@@ -166,7 +166,7 @@
                 <v-text-field
                   v-model="agent.name"
                   :label="tm('form.nameLabel')"
-                  :rules="[v => !!v || 'Name is required', v => /^[a-z][a-z0-9_]*$/.test(v) || 'Lowercase letters, numbers, underscore only']"
+                  :rules="[v => !!v || tm('messages.nameRequired'), v => /^[a-z][a-z0-9_]*$/.test(v) || tm('messages.namePattern')]"
                   variant="outlined"
                   density="comfortable"
                   hide-details="auto"
@@ -215,7 +215,7 @@
             <v-col cols="12" md="6">
               <div class="h-100">
                 <div class="text-caption font-weight-bold text-medium-emphasis mb-2 ml-1">
-                  PERSONA PREVIEW
+                  {{ tm('cards.personaPreview') }}
                 </div>
                 <PersonaQuickPreview
                   :model-value="agent.persona_id"
@@ -231,17 +231,17 @@
     <!-- Empty State -->
     <div v-if="cfg.agents.length === 0" class="d-flex flex-column align-center justify-center py-12 text-medium-emphasis">
       <v-icon icon="mdi-robot-off" size="64" class="mb-4 opacity-50" />
-      <div class="text-h6">No Agents Configured</div>
-      <div class="text-body-2 mb-4">Add a new sub-agent to get started</div>
+      <div class="text-h6">{{ tm('empty.title') }}</div>
+      <div class="text-body-2 mb-4">{{ tm('empty.subtitle') }}</div>
       <v-btn color="primary" variant="tonal" @click="addAgent">
-        Create First Agent
+        {{ tm('empty.action') }}
       </v-btn>
     </div>
 
     <v-snackbar v-model="snackbar.show" :color="snackbar.color" timeout="3000" location="top">
       {{ snackbar.message }}
       <template #actions>
-        <v-btn variant="text" @click="snackbar.show = false">Close</v-btn>
+         <v-btn variant="text" @click="snackbar.show = false">{{ tm('actions.close') }}</v-btn>
       </template>
     </v-snackbar>
   </div>