Make file uploads work on any device or network

Update the file upload URL generation to use same-origin paths, ensuring compatibility across different network environments and devices by allowing the browser to automatically resolve the correct origin.

Replit-Commit-Author: Agent
Replit-Commit-Session-Id: 77cfe984-2c65-4152-bb7a-0df28274fe66
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artifacts/api-server/src/lib/objectStorage.ts

@@ -160,13 +160,21 @@ class LocalDriver implements StorageDriver {
     ).toString("base64url");
     const sig = createHmac("sha256", LOCAL_HMAC_SECRET).update(payload).digest("base64url");
     const token = `${payload}.${sig}`;
-    const base = (process.env.PUBLIC_BASE_URL ?? `http://localhost:${process.env.PORT ?? "8080"}`).replace(/\/+$/, "");
-    return `${base}/api/storage/_local/upload?token=${token}`;
+    // Return a SAME-ORIGIN path (not an absolute URL). The browser will
+    // resolve it against `window.location.origin`, so the upload always
+    // targets the public host the SPA is being served from — works for
+    // localhost, Tailscale (tx.local), LAN IPs, and remote phones alike
+    // without depending on PUBLIC_BASE_URL being set correctly.
+    return `/api/storage/_local/upload?token=${token}`;
   }
 
   parseUploadUrl(rawUrl: string): { bucketName: string; objectName: string } | null {
     try {
-      const u = new URL(rawUrl);
+      // Accept BOTH legacy absolute URLs (older signed URLs still in the
+      // wild) and the new same-origin paths. URL() needs a base for the
+      // relative form — the base is irrelevant since we only read
+      // pathname/searchParams.
+      const u = new URL(rawUrl, "http://placeholder.local");
       if (!u.pathname.endsWith("/api/storage/_local/upload")) return null;
       const token = u.searchParams.get("token");
       if (!token) return null;