Configures Contrast agent services and instrumentation within an application.
@contrast/agent calls agentify at startup. Agentify composes the agent's
infrastructure components (config, logger, patcher, rewriter, reporter, and
others) onto core, then runs a callback that composes the features. After
composition, it calls each component's install() in the order given by the
installOrder option. A component whose name isn't in installOrder is never
installed.
For CommonJS, installation runs just before the application's main module. For
ES modules, it runs after @contrast/esm-hooks is composed. If startup fails, agentify logs
the error and the application runs without instrumentation.