test: cover tool-handler request-shaping and response-mapping logic

[asachs01]

Summary

• afkbot-mcp registers 5 MCP tools (create_pto_request, list_pto_requests, get_pto_request, cancel_pto_request, team_calendar) whose surface was wired in src/index.ts and covered by external smoke/mcp-assert checks, but none of the individual handler functions in src/tools/*.ts were ever invoked by a test. The only existing test file (src/client/afkbotClient.test.ts) covers the client-level getBaseUrl/cleanEnv helpers, not the handlers.
• This repo already uses Node's built-in node --test runner (not Vitest, unlike most of the fleet's other *-mcp repos) — confirmed via package.json's test script and the existing test file's conventions (node:test + node:assert/strict, .test.ts co-located next to source, compiled by tsc into dist/**/*.test.js).
• Adds one test file per handler, following that existing convention: createPtoRequest.test.ts, listRequests.test.ts, getRequest.test.ts, cancelRequest.test.ts, teamCalendar.test.ts. Each mocks the underlying afkbotClient.ts exports via node:test's mock.module(), invokes the exported handler directly, and asserts both the outbound call shape (e.g. end_date defaulting to start_date, status: "all" becoming undefined, limit defaulting to 25) and the response transformation (JSON-wrapped content payload, team_calendar's summary mapping and empty-state message).
• mock.module() is experimental and needs --experimental-test-module-mocks; added that flag to the test script. Verified working on both Node 20.20.2 and 22.23.2 (the CI matrix versions) before relying on it.
• ci.yml previously ran npm ci / npm run lint / npm run build / docker build only — it never actually ran npm test, so the pre-existing client tests weren't enforced either. Added npm test as a CI step so this (and future) coverage is gated, not just present.

Noted, not fixed (scope discipline — flagging, not changing)

• listRequests.ts: limit: params.limit || 25 will silently override an explicit limit: 0 with 25, since 0 is falsy. Probably harmless in practice (nobody wants zero results) but it's a real || vs ?? bug if anyone ever relies on limit: 0.
• Test files are compiled into dist/ by tsc (per tsconfig.json's include: ["src/**/*"]) and the Dockerfile copies the whole dist/ directory into the production image, so compiled test files ship in the runtime image. This was already true before this PR (the existing afkbotClient.test.ts already had this property) — not introduced or changed here.

Test plan

• npm run build (tsc) — clean on Node 20.20.2 and 22.23.2
• npm run lint (tsc --noEmit) — clean on both
• npm test — 23/23 passing on both Node 20.20.2 and 22.23.2
• docker build -t afkbot-mcp:test . — succeeds

Note on repo location

The task that generated this PR assumed afkbot-mcp had migrated to the WYRE-AI GitHub org (per the 2026-08-24/25 org migration covering the other *-mcp repos). Verified this repo has not migrated — WYRE-AI/afkbot-mcp 404s; the live, non-archived, non-fork repo is still wyre-technology/afkbot-mcp. This PR is opened against the actual current location.

🤖 Generated with Claude Code

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