feat: integrate OIDC token exchange in GitHub Action

- Add setupGitHubInstallationToken utility for OIDC token generation
- Implement automatic token exchange with Pullfrog API endpoint
- Add support for multiple authentication methods (input, env, OIDC)
- Create setup utilities for test repository management
- Update action entry point to handle new token flow
- Add environment variable documentation for API key
- Remove large bundled dependencies and optimize build
- Support both development and production token workflows

index.ts

@@ -3,6 +3,11 @@
  * This exports the main function for programmatic usage
  */
 
-export { main } from "./main";
 export { ClaudeAgent } from "./agents";
 export type { Agent, AgentConfig, AgentResult } from "./agents/types";
+export {
+  type ExecutionInputs,
+  type MainParams,
+  type MainResult,
+  main,
+} from "./main";