Update the `Catalog` controller to use a `Storage` interface

[everettraven]

As part of implementing the RFC for catalogd's content storage and serving mechanism and following #113 we need to update the Catalog controller to use the Storage interface for storing catalog content after it is unpacked.

This functionality should be feature gated.

Acceptance Criteria

• Updates Catalog controller to have and use a Storage interface
• Adds a feature gate to enable use of the functionality
• Updates unit/e2e tests as necessary

[everettraven]

/assign

[everettraven]

/assign @anik120

/unassign