[Bug]: Add Enable/disable support for custom templates

[Tharanidk]

Please select the area the issue is related to

AI Workspace

Please select the aspect the issue is related to

Aspect/UI (Frontend layouts, components, styling)

Description

Custom LLM provider templates have no enable/disable support. Once a template is created,
The only way to remove it from the provider listing is to delete it, which is irreversible.

There is no way to temporarily take a template out without permanently losing the template and its configuration.

Expected behaviour:

• Custom LLM provider templates can be enabled or disabled from the AI Workspace.
• A disabled template is hidden from the provider listing but is not deleted, and can be
  re-enabled at any time.
• Deletion remains available for custom templates.

Steps to Reproduce

1. Log in to the AI Workspace.
2. Navigate to LLM Provider Templates.
3. Create a custom LLM provider template (or select an existing custom template).
4. Open the template's actions/overview and look for a way to disable it.

Severity Level of the Issue

Severity/Minor (Non-critical functionality. Can be fixed in future releases)

Environment Details (with versions)

No response