fix: render one-month record ages

[MFA-G]

Summary

• roll age formatting from days to months at 30 days instead of 60
• add MCP search coverage for a 30-day-old record rendering as 1mo

Closes #37

Validation

• npm run test --workspace packages/agentctx -- test/mcp/tools.test.ts
• npm run typecheck --workspace packages/agentctx
• npm run lint

[Deepam02]

Hi @MFA-G
Please rebase and resolve the merge conflicts.

[MFA-G]

Thanks @Deepam02 — I've merged the latest upstream/main into this branch to resolve the conflicts. The merge was clean (auto-merge handled tools.ts and tools.test.ts), and the full suite passes locally: npm run typecheck, npm run lint (biome, 92 files clean), and npm run test (298 tests, all green). The one-line formatAge fix and its regression test are intact. Ready for another look.