Env Config Reader

Use config_reader.py and config_reader.ts to read only the specific environment variables this skill needs (HOME, PORT, LOG_LEVEL, NODE_ENV) via targeted accessors. The setup.sh helper uses set -euo pipefail and only targeted lookups such as printenv PATH. The filter-env.sh helper keeps a documented public prefix with grep instead of dumping the complete environment.

This skill never enumerates or serialises the whole environment; it does not call os.environ.items() or pipe unfiltered env to another command.