docs: Update configuration docs to redirect to module configuration

[exaby73]

Fixes: serverpod/serverpod#4731

[marcelomendoncasoares]

Only one minor question for clarification!

[developerjamiu]

Two things blocking this from progressing:

1. Marcelo's follow-up question on Jan 9 about whether module:auth:AuthUser actually resolves (since AuthUser is declared in serverpod_auth_core and not exported from serverpod_auth_idp) is still unanswered. He proposed two paths: change the module reference to core, or add the export to the IDP package's central export file. Could you confirm which way the framework team wants to go and update accordingly?
2. The branch has merge conflicts with main. A rebase will be needed before this can land.

Happy to give it another pass once both are sorted.

[marcelomendoncasoares]

Two things blocking this from progressing:

1. Marcelo's follow-up question on Jan 9 about whether module:auth:AuthUser actually resolves (since AuthUser is declared in serverpod_auth_core and not exported from serverpod_auth_idp) is still unanswered. He proposed two paths: change the module reference to core, or add the export to the IDP package's central export file. Could you confirm which way the framework team wants to go and update accordingly?
2. The branch has merge conflicts with main. A rebase will be needed before this can land.

Happy to give it another pass once both are sorted.

The only actual possibility is to fix the reference to core. The YAML analyzer loads the models from disk at the module location, so it can't benefit from exports the way we would expect from dart models.