5 - Implement full collections management + Browse tab visibility rules

[jrcastro2]

Implement UI and backend to manage collections inside communities. Display Browse tab as soon as collections exist (even if sub-communities are disabled). Allow community managers to add/edit/delete collections, including a search preview for validating queries before saving. Use UbiquityPress implementation as reference (Esteban can share code).

Tasks:

• Show Browse tab whenever the community has collections.
• Display collections nicely inside the Browse tab.
• Implement CRUD UI for collections in community settings.
• Add search preview when creating/editing a collection query.
• Prepare UI mockups for validation before implementation.
• Review UbiquityPress implementation and adapt relevant logic.

Image is a static path at the moment, there is no bucket. For the moment we could use it like that