Add support for whole machine-wide image verification configuration.
Configuration is a set of rules applied top-down to the image reference,
each specifying a specific cosign-based identity or static public key
claim.
Talos provides a machined API to verify an image reference, resolving it
to the digest on the way as needed.
Talos itself hooks up in the image verification process, while
containerd CRI plugin accesses same API via the machined socket.
Signed-off-by: Laura Brehm <laurabrehm@hey.com>
Signed-off-by: Andrey Smirnov <andrey.smirnov@siderolabs.com>
