fix: add /metadata /schema /mcp endpoints for OpenEnv runtime validation

fix: add /metadata /schema /mcp endpoints for OpenEnv runtime validation

fix: rename script entry point to server

fix: pyproject.toml scripts entry, main(), uv.lock, openenv-core dep

fix: add pyproject.toml for openenv validate

fix: move server files into server/ subfolder

initial: ClinicalTrialEnv OpenEnv submission