fix: Remove redact-pii dependency and address security vulnerabilities

[naji247]

Summary

• Remove dependency on redact-pii package due to its outdated transitive dependencies causing security vulnerabilities
• Add pnpm overrides to pin vulnerable transitive dependencies to secure versions
• Update dev dependencies to latest versions (vitest, eslint, etc.)

Security Fixes

The following vulnerabilities are addressed via pnpm overrides:

Package	Vulnerability	Source
js-yaml	GHSA-mh29-5h37-fv8m (prototype pollution)	@changesets/cli
tmp	GHSA-52f5-9888-hmc6 (symlink attack)	@changesets/cli
vite	GHSA-93m4-6634-74q7 and others	vitest
body-parser	GHSA-wqch-xfxh-vrr4 (DoS via URL encoding)	@modelcontextprotocol/sdk
brace-expansion	GHSA-v6h2-p8h4-qcjw (ReDoS)	eslint

Test plan

• Run pnpm install to verify lock file resolves correctly
• Run pnpm test to verify all tests pass
• Run pnpm audit to verify no remaining vulnerabilities