chore: update styles, add splash config, and improve search functionality

- Replace deprecated StyleSheet.absoluteFillObject with StyleSheet.absoluteFill (React Native 0.76+)
- Add splash screen configuration in app.json
- Fix duplicate UIBackgroundModes and add audio mode for iOS
- Disable Android ripple effect on tab bar buttons
- Improve SmartImage loading state to prevent unnecessary re-renders
- Refactor ImageGrid to use mainUri with separate previewUrl for better preview handling
- Add market search support with trade items tab in SearchScreen
- Pass homeTab prop to SearchScreen for context-aware search behavior
- Simplify fetchUnreadCount return type to void in MessageSyncService
- Fix StatusBar import from expo to react-native in ChatScreen

src/stores/message/MessageManager.ts

@@ -208,7 +208,7 @@ class MessageManager {
     return this.syncService.loadMoreMessages(conversationId, beforeSeq, limit);
   }
 
-  async fetchUnreadCount(): Promise<{ totalUnread: number; systemUnread: number }> {
+  async fetchUnreadCount(): Promise<void> {
     return this.syncService.fetchUnreadCount();
   }
 

src/stores/message/services/MessageSyncService.ts

@@ -30,7 +30,7 @@ export class MessageSyncService implements IMessageSyncService {
   /** 正在加载会话列表下一页 */
   private loadingMoreConversations = false;
     /** fetchUnreadCount 去重：复用 in-flight promise */
-  private fetchUnreadCountPromise: Promise<{ totalUnread: number; systemUnread: number }> | null = null;
+  private fetchUnreadCountPromise: Promise<void> | null = null;
 
   constructor(
     getCurrentUserId: () => string | null,
@@ -352,20 +352,19 @@ export class MessageSyncService implements IMessageSyncService {
   /**
    * 获取未读数（去重：复用 in-flight promise）
    */
-  async fetchUnreadCount(): Promise<{ totalUnread: number; systemUnread: number }> {
+  async fetchUnreadCount(): Promise<void> {
     if (this.fetchUnreadCountPromise) {
       return this.fetchUnreadCountPromise;
     }
     this.fetchUnreadCountPromise = this.doFetchUnreadCount();
     try {
-      const result = await this.fetchUnreadCountPromise;
-      return result;
+      await this.fetchUnreadCountPromise;
     } finally {
       this.fetchUnreadCountPromise = null;
     }
   }
 
-  private async doFetchUnreadCount(): Promise<{ totalUnread: number; systemUnread: number }> {
+  private async doFetchUnreadCount(): Promise<void> {
     const store = useMessageStore.getState();
 
     try {
@@ -393,10 +392,8 @@ export class MessageSyncService implements IMessageSyncService {
 
       // 服务端汇总未读为 0：不主动清零本地未读，等 fetchConversations 提供权威数据
       // 避免后端缓存竞态导致的未读数抖动
-      return { totalUnread, systemUnread };
     } catch (error) {
       console.error('[MessageSyncService] 获取未读数失败:', error);
-      return { totalUnread: 0, systemUnread: 0 };
     }
   }