Add comprehensive comments to code changes

[JoshuaAFerguson]

Add detailed JSDoc and GoDoc comments to all files modified in today's commits to improve code maintainability and developer experience.

API Backend (Go):

• api/internal/api/stubs.go: Add comprehensive package-level documentation explaining stub endpoints, backwards compatibility, K8s resource management, compliance stubs, and WebSocket upgrader security configuration
• Enhanced GetMetrics function documentation with data source explanations

WebSocket Hooks (TypeScript):

• ui/src/hooks/useWebSocket.ts: Add detailed JSDoc to all hooks including @param, @returns, @example tags; document custom backoff strategy
• ui/src/hooks/useEnterpriseWebSocket.ts: Add comprehensive JSDoc for enterprise WebSocket hook, useWebSocketEvent, and all 13 predefined event hooks with block comment explaining event types

UI Components (React):

• ui/src/pages/admin/Nodes.tsx: Add file-level JSDoc documenting node management features, operations, workflows, and real-time updates
• ui/src/pages/admin/Compliance.tsx: Add file-level JSDoc documenting compliance frameworks, policy types, violation management, and plugin integration

Documentation Improvements:

• All hooks now have comprehensive JSDoc with parameter descriptions, return value documentation, and usage examples
• Backoff strategy clearly documented (30s, 15s, 15s, then 60s pattern)
• WebSocket security features explained (origin validation, token auth)
• All predefined event hooks have descriptive single-line JSDoc
• Admin pages have comprehensive feature lists and workflow descriptions

Related Files Already Well-Documented:

• api/internal/handlers/nodes.go: Already has excellent documentation
• api/internal/k8s/client.go: Already has comprehensive package docs
• ui/src/pages/admin/Scaling.tsx: Already has detailed JSDoc

This ensures all code changed today is thoroughly documented for future developers and maintainers.