test(template): cover health endpoint dependency status, timeout, and error paths

Replaces the standalone Hono fixture in tests/unit/health.test.ts with
a test that mounts the real healthRoutes inside a Hono parent + requestId
middleware (mirroring index.ts wiring). pingDatabase is mocked via
vi.mock so no real postgres is needed in CI.

Coverage (both Workers and Node test bodies):
- 200 + healthy when DB connected
- version sourced from APP_VERSION (c.env on Workers, process.env on Node)
- numeric uptime >= 0
- 503 + unhealthy when DB disconnected
- 503 on timeout via fake-timer-advanced Promise.race
- 503 on thrown error (never 500)
- requestId preserved in body and X-Request-Id header

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: Paul Mulligan