Externalize configuration of backend services and dockerize

[ChristianUlbrich]

The current design is using a lot of assumptions, hard-coded things and is tightly coupled to Azure. In a first step, we want to be able to run the full stack on any user-supplied Azure services. For this we need to externalize all configuration.

Configuration needs to be externalized and configurable via the environment, most preferably via some .env - compatible mechanism.

Initial goals

We want to be able to run the full stack on our own infrastructure and we want to have a glimpse at the various admin pages. Initially it is perfectly okay, if the stack runs only locally, but leverages remote Azure services. If this is not feasible (CORS, ...) then we have to add real deployment to the stack.

Acceptance criteria

• configuration can be supplied via an .env
• how to create a private instance is documented
• minimal contemporary adjustments for making getting it to run (current LTS of Node, read: 20), current npm install works)
• admin can be configured as well
• stack is dockerized and can be run locally

Out of spec

• apart from that build tooling is not changed at all