Tip - use a database.
Computers are awesome at automating things, that goes for dev tooling as well.
If you’ve touched the ITSM space you’re used to managing and maintaining many thousand of assets. A few hundred microservices is nothing, really.
My team use what you could call a simplified CMDB (configuration management database) which is cross referenced against the service discovery.
The cmdb keep info about every service, such as persistent data-sources, vm’s etc, but most important - relationships: domain, team, services and resources.
A microservice is basically a ”ci” (configuration item) with a managed lifecycle.