revert generateLocalTokens, wrong analysis on game launching issue

backend/managers/gameLauncher.js

@@ -68,11 +68,53 @@ async function fetchAuthTokens(uuid, name) {
     };
   } catch (error) {
     console.error('Failed to fetch auth tokens:', error.message);
-    // Don't use invalid local tokens that cause the game to hang
+    // Fallback to local generation if server unavailable
-    throw new Error(`Authentication server unavailable: ${error.message}. Please check your internet connection or try again later.`);
+    return generateLocalTokens(uuid, name);
   }
 }
 
+// Fallback: Generate tokens locally (won't pass signature validation but allows offline testing)
+function generateLocalTokens(uuid, name) {
+  console.log('Using locally generated tokens (fallback mode)');
+  const authServerUrl = getAuthServerUrl();
+  const now = Math.floor(Date.now() / 1000);
+  const exp = now + 36000;
+
+  const header = Buffer.from(JSON.stringify({
+    alg: 'EdDSA',
+    kid: '2025-10-01',
+    typ: 'JWT'
+  })).toString('base64url');
+
+  const identityPayload = Buffer.from(JSON.stringify({
+    sub: uuid,
+    name: name,
+    username: name,
+    entitlements: ['game.base'],
+    scope: 'hytale:server hytale:client',
+    iat: now,
+    exp: exp,
+    iss: authServerUrl,
+    jti: uuidv4()
+  })).toString('base64url');
+
+  const sessionPayload = Buffer.from(JSON.stringify({
+    sub: uuid,
+    scope: 'hytale:server',
+    iat: now,
+    exp: exp,
+    iss: authServerUrl,
+    jti: uuidv4()
+  })).toString('base64url');
+
+  const signature = crypto.randomBytes(64).toString('base64url');
+
+  return {
+    identityToken: `${header}.${identityPayload}.${signature}`,
+    sessionToken: `${header}.${sessionPayload}.${signature}`
+  };
+}
+
 async function launchGame(playerNameOverride = null, progressCallback, javaPathOverride, installPathOverride, gpuPreference = 'auto', branchOverride = null) {
   // ==========================================================================
   // STEP 1: Validate player identity FIRST (before any other operations)