Function deriveAllKeys

deriveAllKeys(
    globalEnv: readonly PropertyKey[],
    stageEnv: readonly PropertyKey[],
    fnEnv?: readonly PropertyKey[],
): ReadonlySet<PropertyKey>
Derive the union of env keys we plan to expose.
Parameters
- globalEnv: readonly PropertyKey[]
  keys exposed from global params schema
- stageEnv: readonly PropertyKey[]
  keys exposed from stage params schema
- fnEnv: readonly PropertyKey[] = []
  optional per‑function extra keys
Returns ReadonlySet<PropertyKey>
- Defined in src/runtime/envBuilder.ts:18