Rebrand the entire application from "胡萝卜社区" (Carrot BBS) to "威友" (WithYou), including:

- Update app name, package name (skin.carrot.bbs → cn.qczlit.withyou), and bundle identifier
- Update API endpoints (bbs.littlelan.cn → withyou.littlelan.cn)
- Update URL scheme (carrotbbs:// → withyou://)
- Rename database from carrot_bbs to with_you
- Update CI/CD pipeline image names and artifact naming
- Add Android signing configuration for release builds
- Update all UI text and comments throughout the codebase
- Refactor registerStore to use in-memory state instead of AsyncStorage persistence
- Improve WebRTC track handling and call stream management
- Add metro platform resolution for native platform support

BREAKING app package, database, and URLs are no longer valid

src/components/business/ShareSheet/ShareSheet.tsx

@@ -1,4 +1,4 @@
-import React, { useEffect, useMemo } from 'react';
+import React, { useEffect, useMemo } from 'react';
 import { Share as RNShare, Platform } from 'react-native';
 
 export interface ShareSheetProps {
@@ -18,7 +18,7 @@ const ShareSheet: React.FC<ShareSheetProps> = ({
 }) => {
 
   const shareText = useMemo(() => {
-    const title = postTitle || '胡萝卜BBS帖子';
+    const title = postTitle || '威友帖子';
     return `${title} ${postUrl || ''}`;
   }, [postTitle, postUrl]);