Refactor: Move intern/public slot type distinction to API layer

[coderabbitai]

Context

A TODO comment was identified during PR #1878 review indicating an architectural improvement opportunity.

TODO Comment Location: zmsdb/src/Zmsdb/Query/SlotList.php:347
Comment: TODO Unterscheidung nach intern/public sollte erst nach der API erfolgen!
Translation: "TODO: The distinction between intern/public should only happen after the API!"

Added by: matthilo96 on 2026-01-30
Related Commit: a357f64 (feat(ZMSKVR-1164): remove callcenter from all files)

Problem

Currently, the slotType parameter ('public' or 'intern') is being passed through multiple architectural layers:

• API layer (zmsapi)
• Database layer (zmsdb)
• Query layer (Query/SlotList.php)

This violates separation of concerns - business logic about slot type distinctions should not be handled at the database/query layer.

Proposed Solution

Refactor the architecture so that:

1. The API layer handles the slotType distinction
2. The database/query layer remains agnostic to business logic
3. The API layer filters or processes results based on slot type after retrieval

This would improve:

• Separation of concerns
• Testability
• Maintainability
• Layer independence

Related

• PR: feat(ZMSKVR-1164): remove callcenter from the opening hours configuration #1878
• Comment: feat(ZMSKVR-1164): remove callcenter from the opening hours configuration #1878 (comment)
• Related work: ZMSKVR-1164 (callcenter removal)
• Requested by: @ThomasAFink