API Endpoint Versioning Issue: Inconsistent Behavior Across Versions

Hello NextCloud Deck Team,

I've encountered an unexpected behavior when interacting with the Deck API, specifically regarding the versioning of API endpoints.

Issue Description:
While using the Deck API, I noticed that calls to different API versions are yielding the same results, regardless of the version number specified. This behavior is inconsistent and potentially misleading, as one would expect different API versions to exhibit different behaviors or return different data structures.

Steps to Reproduce:

1. Make an API call to SITE_URL/apps/deck/api/v1.0/boards/1. Observe the response.
2. Repeat the API call with a different version number, for example, SITE_URL/apps/deck/api/v1.1/boards/1 or even a non-existent version like SITE_URL/apps/deck/api/v9.99/boards/1.
3. Notice that all these calls return the same response, regardless of the version number specified.

Expected Behavior:
API calls to different versions should correspond to the specific behavior and data structure defined for that version. Moreover, calls to non-existent API versions should return an error, indicating the invalid version.

Actual Behavior:
The API responds identically to calls across different version numbers, including non-existent versions.

Impact:
This behavior could lead to confusion and potential issues, especially for developers relying on specific versioning for feature compatibility and data structure consistency.

I'm looking forward to your feedback on this issue. Thank you for your hard work on NextCloud Deck, and I'm eager to see how this issue can be resolved to improve the platform's reliability and predictability.

Best regards,
Ernesto

Start by tracing the API entry points for /apps/deck/api/v1.0/boards/1, /apps/deck/api/v1.1/boards/1, and /apps/deck/api/v9.99/boards/1. Compare how supported and unknown version values are handled and identify the expected version-specific behavior. Done means supported versions behave according to their definitions and an unknown version returns an error.