[Feature Request] Add Skills and Hooks for Extensible Multi-Agent Workflows

[Junyi-99]

adding a Skills and Hooks system similar to what Anthropic Claude offers. This would enable modular, reusable, and event-driven extensions to PaperDebugger's AI agents.

Skills would allow:

• Encapsulating reusable tasks (e.g., document formatting, structured review passes, citation checks)
• Sharing and reusing custom workflows across projects
• Creating pre-defined, step-by-step AI actions that can be automatically invoked

Hooks would allow:

• Triggering custom scripts or workflows at specific events (e.g., before/after AI suggestion insertion, on document save, or on user prompt submission)
• Enabling auditing, notifications, or automated checks integrated with AI workflows
• Providing developers flexibility to extend PaperDebugger safely without modifying the core codebase

This system would make PaperDebugger even more extensible, allowing researchers and developers to create richer, automated, and project-specific AI workflows.

[4ndrelim]

Should we outline the list of skills and the expected result of each? or is this still in an explorative phase? @Junyi-99 @kah-seng