feat: make Gitea optional

[CasLubbers]

Only merge with:

• feat: BYO Git apl-core#2914
• feat: make api work with external Git source apl-api#915

Considerations

• I have tested the changes in both light and dark mode.
• I have considered the need for new unit tests.
• I have tested the changes on a cluster.
• I have included relevant documentation updates.
• I have an approved Figma design or have reflected my changes in Figma
• I have verified that the UI/UX is consistent in major browsers (e.g., Chrome, Firefox, Safari, Edge).
• I have tested the changes for responsiveness in different screen resolutions.
• I have tested expected error states and verified that the user is presented with informative error messages.
• I have tested the feature with unusual or extreme inputs (e.g., very long strings, empty states, clicking a button multiple times quickly).

[ferruhcihan]

We should handle this line properly, there is no repo prop, so it always uses the gitea url as a fallback.

[dennisvankekem]

the code does what it's supposed to do, but we might want to think about supporting external Gitea sources, but that is out of scope for this implementation