[bug/ux] don't know what catalog image tag I was using before

[perdasilva]

Say we create a ClusterCatalog pointing to my-catalog:1 and it succeeds, we then go and point to my-catalog:2, which maybe doesn't exist. If you inspect the conditions you can see:

• the error (@ generation n)
• that it's available (@ generation n - 1)
• the image reference my-catalog@sha256...

The issue is that it's not trivial to recover the original image (i.e. my-catalog:1), since we resolve to the sha'ed image reference.

Maybe we should either:
a) include the original input in the resolved source stanza to look something like:

resolvedSource:
image:
  lastSuccessfulPollAttempt: "2024-10-10T07:12:43Z"
  image: my-catalog:1
  ref: my-catalog@sha256:2f6ba3fc28b4ef4b99027855681be8b8fe0962d931afc1ca5120f626f7416486
type: Image

b) make .spec.source immutable once set