UX: improve messages / warnings /errors to include platform (os/arch/xx)

[thaJeztah]

related to docker/for-linux#1170 (comment)
also related (should be done in conjunction with these changes); #42283

We should improve some message to include the (expected) platform, for example:

Unable to find image 'pihole/pihole:v5.2.1' locally

This could include the desired os/architecture, e.g.:

Unable to find image 'pihole/pihole:v5.2.1' for platform linux/arm64

The pull output could also include a line with the platform/architecture that was pulled;

v5.2.1: Pulling from pihole/pihole
aceecb32d1c3: Pull complete
...
Digest: sha256:7888e89f4d435673c75896c546fefe3177379c99c8766c89be25a905f8def533
Status: Downloaded newer image for pihole/pihole:v5.2.1

e.g.;

v5.2.1: Pulling from pihole/pihole (platform: linux/arm64)
aceecb32d1c3: Pull complete
...
Digest: sha256:7888e89f4d435673c75896c546fefe3177379c99c8766c89be25a905f8def533
Platform: linux/arm64
Status: Downloaded newer image for pihole/pihole:v5.2.1

Or splitting the fields (not sure if "os-features" and "variant" are part of the OCI spec now)

Digest: sha256:7888e89f4d435673c75896c546fefe3177379c99c8766c89be25a905f8def533
Platform: os: linux, architecture: arm64, variant: xxx, os-features: xxx
Status: Downloaded newer image for pihole/pihole:v5.2.1

[thaJeztah]

Discussing in the maintainers meeting; we should also print a warning after pulling a (single-arch) image, and the pulled image didn't match either the specified --platform or didn't match the native/default arch

[tianon]

Discussing again in the maintainers meeting today, we came back to this issue to note that the digest of the actual image that was pulled from a manifest list is also as relevant as the platform. 👀

Edit: 😂 very related to (my own issue): docker/roadmap#262

[thaJeztah]

I should probably (re)write this ticket, or split some parts to separate tickets, one of them for improving "pull progress", and post some mock-ups that we created for this to make the output more user-friendly, but also to provide information that may be relevant to the image (depending on what features are available, which could include information about attestations, signing etc)