Agl-lite: A Minimal Workable Version of Agent Lightning

This project agl-lite which is a minimal workable version of the popular agentic rl project Agent Lightning (https://github.com/microsoft/agent-lightning).

here are some key changes:

1. remove the dependency of litellm and build self-owned request gateway instead;
2. remove the dependency of OpenTelemetry and the whole stack built upon it, such as the tracers of agents; instead, use gateway to collect request-response data during transfer and record them into data store;
3. following (2), the organization of data is not based on span in opentelemetry, instead, the basic trajectory format is sequence of requests (with response);
4. use kubenetes as the default agent runner (minikube for single machine), and move the retry control from data store to k8s controller, and simplify the rollout states

Instruction for Coding Agents

The architecture of agl-lite is described in the high-level architecture design doc in docs/design/0_architecture.md, you should read it to get the overall picture of the system. Since the document is quite long, you should first read the TOC by greping ## in the markdown file, and then read the sections you are interested in.

There are some local environment setup and configuration needed for this project refactoring in .local/.