Path to a JS/TS entrypoint file for a QuickJS REPL module, relative to the skill directory.
Warning: this is experimental.
When present, consumers of this metadata (notably langchain-quickjs's
CodeInterpreterMiddleware) may install the skill as a dynamic-importable ES
module. The string is a POSIX path like ./index.ts pointing at a
file inside the skill dir. This middleware only parses and validates
the field — it does not load or execute any JavaScript.
