feat: add third-party model support (#592)

- Support ANTHROPIC_BASE_URL and ANTHROPIC_AUTH_TOKEN for custom API endpoints
- Add documentation for third-party/open-source model usage

Co-authored-by: wenglixin <wenglixin@menusifu.cn>

src/container-runner.ts

@@ -204,7 +204,12 @@ function buildVolumeMounts(
  * Secrets are never written to disk or mounted as files.
  */
 function readSecrets(): Record<string, string> {
-  return readEnvFile(['CLAUDE_CODE_OAUTH_TOKEN', 'ANTHROPIC_API_KEY']);
+  return readEnvFile([
+    'CLAUDE_CODE_OAUTH_TOKEN',
+    'ANTHROPIC_API_KEY',
+    'ANTHROPIC_BASE_URL',
+    'ANTHROPIC_AUTH_TOKEN',
+  ]);
 }
 
 function buildContainerArgs(