Make the Substrate API a distinct service

[dillu24]

Technical Story

For more scalability and easier maintenance it is ideal that the Substrate-API service we developed for PANIC is offered as a separate open source service. This would be similar to what we have done for the Polkadot API Server

Requirements

• Migrate Substrate-API code-base to a new public repo on github
• Write documentation on this new repo
• Publish new repo.
• Remove Substrate-API code base from the Alerter service
• Add Substrate-API docker image to DockerHub on Simply VC's repo
• Make use of the dockerhub image inside PANIC's docker-compose.yml file
• Depracate the old Polkadot API Server and write a note in the README.MD file to point towards the new repo (see panic_cosmos or panic_polkadot as examples).