fix: 改进音乐API代理的图片端点处理，将JSON响应转换为重定向

sync-server/server.js

@@ -310,7 +310,8 @@ function downloadFile(url, dest) {
 
 // --- Music API Proxy Function ---
 function proxyRequest(targetUrl, req, res) {
-    const parsedTarget = url.parse(targetUrl);
+    const parsedTarget = url.parse(targetUrl, true);
+    const isPicRequest = parsedTarget.query && parsedTarget.query.type === 'pic';
     
     const options = {
         hostname: parsedTarget.hostname,
@@ -325,6 +326,53 @@ function proxyRequest(targetUrl, req, res) {
     };
 
     const proxyReq = https.request(options, (proxyRes) => {
+        const passThrough = () => {
+            const headers = { ...proxyRes.headers };
+            delete headers['content-encoding'];
+            delete headers['transfer-encoding'];
+            
+            res.writeHead(proxyRes.statusCode, headers);
+            proxyRes.pipe(res);
+        };
+
+        // pic endpoint now returns JSON, turn it into a redirect for <img>
+        if (isPicRequest) {
+            if (proxyRes.statusCode >= 300 && proxyRes.statusCode < 400 && proxyRes.headers.location) {
+                res.writeHead(302, { Location: proxyRes.headers.location });
+                proxyRes.resume();
+                res.end();
+                return;
+            }
+
+            const contentType = proxyRes.headers['content-type'] || '';
+            if (contentType.startsWith('image/')) {
+                passThrough();
+                return;
+            }
+
+            let body = '';
+            proxyRes.setEncoding('utf8');
+            proxyRes.on('data', chunk => body += chunk);
+            proxyRes.on('end', () => {
+                try {
+                    const parsedBody = JSON.parse(body);
+                    if (parsedBody && parsedBody.url) {
+                        res.writeHead(302, { Location: parsedBody.url });
+                        res.end();
+                        return;
+                    }
+                } catch (e) {
+                    // fall through
+                }
+
+                res.writeHead(proxyRes.statusCode || 200, {
+                    'Content-Type': proxyRes.headers['content-type'] || 'application/json'
+                });
+                res.end(body);
+            });
+            return;
+        }
+
         // Handle redirects
         if (proxyRes.statusCode >= 300 && proxyRes.statusCode < 400 && proxyRes.headers.location) {
             // For redirects, return the redirect URL to client
@@ -333,13 +381,7 @@ function proxyRequest(targetUrl, req, res) {
             return;
         }
 
-        // Copy response headers (except problematic ones)
+        passThrough();
-        const headers = { ...proxyRes.headers };
-        delete headers['content-encoding'];
-        delete headers['transfer-encoding'];
-        
-        res.writeHead(proxyRes.statusCode, headers);
-        proxyRes.pipe(res);
     });
 
     proxyReq.on('error', (e) => {