feat(ai-chat): 动态切换输入框 placeholder 文案，支持语音和媒体附件提示

lang/en-us/ai-chat/index.js

@@ -152,6 +152,11 @@ export const lang = {
 	releaseToSend: 'Release to send',
 	releaseToCancel: 'Release to cancel',
 	slideUpToCancel: '↑ Slide up to cancel',
+	slideUpToCancelHint: '↑ Slide up to cancel',
+	// PR-INPUT-PLACEHOLDER-DYNAMIC (2026-09-28): dynamic input placeholder by context
+	placeholderDefault: 'Type a message or hold to talk',
+	placeholderWithAudio: 'Add a note for your voice (optional)',
+	placeholderWithMedia: 'Add a caption (optional)',
 	slideUpToCancelHint: '↑ Release to cancel',
 	voiceStartFailed: 'Cannot start recording',
 	voiceStopFailed: 'Recording failed, please try again',

lang/zh-cn/ai-chat/index.js

@@ -152,6 +152,11 @@ export const lang = {
 	releaseToCancel: '松开取消',
 	slideUpToCancel: '↑ 上滑取消',
 	slideUpToCancelHint: '↑ 松开取消',
+	// PR-INPUT-PLACEHOLDER-DYNAMIC (2026-09-28): 输入框 placeholder 按上下文动态切换
+	//   默认 / 有语音附件 / 有其他媒体附件, 三态文案互不冲突
+	placeholderDefault: '发消息或按住说话',
+	placeholderWithAudio: '给语音留言加个说明（可选）',
+	placeholderWithMedia: '添加文字说明（可选）',
 	voiceStartFailed: '无法开始录音',
 	voiceStopFailed: '录音失败，请重试',
 	voiceNotSupported: '当前平台不支持语音输入',

pages_tool/ai-chat/ai-chat-message.vue

@@ -472,7 +472,7 @@
               ref="messageInput"
               v-model="inputText"
               class="message-input"
-              placeholder="发消息或按住说话"
+              :placeholder="inputPlaceholder"
               placeholder-class="message-input-placeholder"
               :maxlength="chatUiConfig.ui_input_max_length"
               :auto-height="true"
@@ -885,6 +885,23 @@ export default {
       if (this.voiceHoldCancelling) return this.$lang('ai-chat.index.releaseToCancel')
       if (this.voiceHolding) return this.$lang('ai-chat.index.releaseToSend')
       return this.$lang('ai-chat.index.holdToTalk')
+    },
+    // PR-INPUT-PLACEHOLDER-DYNAMIC (2026-09-28): 输入框 placeholder 按上下文动态切换
+    //   - 有待发语音附件 → 提示"给语音加说明"
+    //   - 有待发图片/文件/视频附件 → 提示"添加文字说明"
+    //   - 默认态 → 提示"发消息或按住说话"
+    //   优先级: 语音 > 其他媒体 > 默认
+    inputPlaceholder() {
+      const files = this.pendingFiles || []
+      const hasAudio = files.some(f => f && f.type === 'audio')
+      if (hasAudio) {
+        return this.$lang('ai-chat.index.placeholderWithAudio') || '给语音留言加个说明（可选）'
+      }
+      const hasMedia = (this.pendingImages && this.pendingImages.length) || files.length > 0
+      if (hasMedia) {
+        return this.$lang('ai-chat.index.placeholderWithMedia') || '添加文字说明（可选）'
+      }
+      return this.$lang('ai-chat.index.placeholderDefault') || '发消息或按住说话'
     }
   },
                // 新增：组件销毁时清除所有定时器