feat: Add Token Vesting Agent for bounty #2

[flashlib]

Summary

Type of Change

• New AI Agent
• Bug fix
• New feature
• Breaking change
• Documentation update
• Smart contract change
• SDK enhancement
• CI/CD / DevOps

Changes Made

Testing

• Unit tests pass (make test)
• Local dev server runs without errors (make dev)
• Agent responds to /health, /manifest, /execute endpoints
• Smart contracts compile and tests pass (forge test)
• Dashboard builds without errors (npm run build)

Agent-Specific Checklist

• Agent has a unique id (lowercase, hyphens only)
• Agent includes .env.example with required variables
• Agent registers successfully via npm run register
• Agent handles edge cases gracefully (missing payload, invalid wallet, etc.)
• Agent returns proper response format with status, result, and executionTimeMs

Screenshots / Output

Additional Context

[paypol-protocol]

Changes Requested

The Token Vesting Agent implementation looks solid - good natural language parsing and vesting calculations. However:

Must Fix

1. PR description is empty - Please fill in the PR template (Summary, Changes, Testing sections)
2. ethers version mismatch - You use ethers v6.9.0 but the project standard is v6.16.0. Please update.
3. Generated Solidity code - The inline contract template should have a security disclaimer noting it is unaudited scaffold code.

Nice to Have

• Add unit tests for the natural language parser
• Consider edge cases: zero tokens, negative amounts, past start dates

Please update the PR description and address the ethers version. The code itself is good work