mgr/dashboard: work with RBD images v1

mgr/dashboard: work with RBD images v1

Add support for RBD Image Format v1:
- This format lacks ID field, required for dashboard. Instead,
RBD image `block_name_prefix` is used as unique ID (together with pool
id and namespace)
- Additionally, `image_format` is now exposed.
- In the front-end side:
  - Copy action on a v1 image will cause the image to be copied to v2
format.
  - List doesn't allow Move to Trash on v1 images,
  - Details section now shows `image_format` for images,
  - Edit Form disables flags not supported for v1 (`deep-flatten`,
`layering`, `exclusive-lock`).
  - Protect does not work on v1 images or v2 images created from v1
ones.

Fixes: https://tracker.ceph.com/issues/36354
Signed-off-by: Ernesto Puerta <epuertat@redhat.com>