add: openenv-core dependency required for hackathon evaluator

feat: unlimited agents support with fixed build configuration

chore: update dependencies and environment configuration for unlimited agent support

Simplify pyproject.toml

Update pyproject.toml format to match OpenEnv example

Fix server entry point and add __init__.py

Add openenv-core dependency and server entry point

final: absolute comprehensive synchronization - capturing server fixes - 00:51

verify: absolute forced sync marker 00:47

final: definitive release synchronization including pyproject.toml - 00:43