[FEAT] Move `db get-endpoint *` to `db endpoints *`

[toptobes]

To help declutter the database subcommands, the follow commands could live under a single db endpoints subcommand:

get-endpoint-swagger      Get the SwaggerUI endpoint for the specified
                            database
get-endpoint-api          Get the API endpoint to interact with the specified
                            database
get-endpoint-playground   Get the GraphQL Playground for the specified
                            database

This would also make such commands more extensible (e.g. adding db endpoints data-api) without overshadowing other db commands

Old db get-endpoint-* commands would still work, but they would be hidden from the helptext, and issue a deprecation warning if used, redirecting users to db endpoints *.