Function validateSkillCapabilities

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

validateSkillCapabilities(
capabilities: SkillCapabilities,
): Result<void, SkillSecurityError>
Validates capabilities against security constraints.
Parameters
- capabilities: SkillCapabilities
  The capabilities to validate
Returns Result<void, SkillSecurityError>
Result indicating success or validation error
- Defined in packages/nexus-agents/src/agents/skills/skill-security.ts:241