Allow customization of tags, maybe with a prefix

[gadomski]

Right now the route tags are hardcoded, e.g.

pystapi/stapi-fastapi/src/stapi_fastapi/routers/root_router.py

Line 94 in 0f36066

tags=["Root"],

. If we include stapi-fastapi as a sub-router in another FastAPI app, we might want to customize those tags, e.g. with a prefix (stapi-root, for example).