feat: add moderation and rate limiting system

[sanzzzz-g]

Description of Changes

Implemented an advanced moderation and rate-limiting system for Chat Buddy to improve platform stability, spam prevention, and message safety.

Features Added

• Blocked inappropriate/profane messages using moderation utilities
• Added duplicate message detection
• Implemented basic rate limiting for rapid consecutive messages
• Added spam/flooding detection improvements in agent guardrails
• Added moderation tracking helpers
• Added moderation-related TypeScript interfaces
• Added unit tests for moderation and rate-limiting functionality

Technical Changes

• Created src/utils/moderation.ts
• Updated messageHandler.service.ts to integrate moderation checks
• Updated agent.guardrails.ts with spam/flooding prevention rules
• Extended shared types in src/types/types.ts
• Added dedicated moderation and rate-limit test suites

These changes improve abuse prevention while keeping the implementation lightweight and maintainable.

---

Related Issue Number

Fixes #34

---

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Refactor or other maintenance

---

How Was This Tested?

Tested using:

• npm test
• npx vitest

Verified Scenarios

• Profanity/blocked word detection
• Duplicate message prevention
• Rapid message rate limiting
• Safe messages passing moderation checks
• Existing debounce logic functionality

---

Checklist

• The code builds without errors (npm run build).
• Existing tests pass (npm test).
• New tests have been added if needed.
• Documentation has been updated to reflect these changes if needed.

[sanzzzz-g]

hey @snackoverflowasad I have opened PR kindly review it!

[sanzzzz-g]

hey @snackoverflowasad I have opened PR kindly review it!

[shouri123]

@sanzzzz-g i have reviewed the chnages there is no checks running please fix that