fix: pass logger instances via loggerInstance (fastify v5 rejects instances in logger)

[kilisamemarisaaa]

Summary

fastify v5 only accepts a configuration object in the logger option and throws FST_ERR_LOG_INVALID_LOGGER_CONFIG when given an instance — instances must go through loggerInstance. fastify-cli converges user-provided logger instances — from --logging-module (#775), --options files (the setup described in #574), or server options — into options.logger, so passing a real Pino instance crashes fastify start at startup:

FastifyError [Error]: logger options only accepts a configuration object.
    code: 'FST_ERR_LOG_INVALID_LOGGER_CONFIG'

This was invisible to the suite because the only logger tests use a config-object fixture (test/data/custom-logger.js = { name, customLevels: {...} }); the instance path had zero coverage.

Fix: after all option merges converge in start.js, route any logger value exposing child() to loggerInstance (4 lines). Config-object loggers (including the existing fixtures and the { level } default) are untouched.

Regression test: -L with a fixture exporting a real Pino instance; asserts the logger level survives into fastify.log.

Verification

• npm run lint clean
• Current head is one commit based directly on main; it does not include fix: restore CI test execution and repair CJS/CLI regressions from dependency bumps #910
• Important CI caveat: suite-runner.js on current main still calls glob's removed callback API, so the green JS-suite jobs exit without running the tests. fix: restore CI test execution and repair CJS/CLI regressions from dependency bumps #910 fixes that runner; after it lands, this branch must be updated and the logger regression test revalidated before merge.

[Tony133]

There are the same commits as in this PR: #910 Can you create a clean PR with the changes described? Or do a rebase?