Function validateSkillRBAC

Skills module exports (Voyager-style skill library) - Issue #528 Split from agents.ts for file size compliance (Issue #285)

validateSkillRBAC(rbac: SkillRBAC): Result<void, SkillSecurityError>
Validates RBAC configuration.
Parameters
- rbac: SkillRBAC
  The RBAC configuration to validate
Returns Result<void, SkillSecurityError>
Result indicating success or validation error
- Defined in packages/nexus-agents/src/agents/skills/skill-security.ts:279