🐛 Move kairos vars to their own file

[Itxaka]

Otherwise when creating derivatives, the upgrades can overwrite the existing kairos release info adn break the whole thing.

This patch adds the variables into a new /]etc/kairos-release file, as well as keeping them in the usual /etc/os-release file for backwards compatibility

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):

Part of: #2907

[Itxaka]

This needs an updated agent bundled with the changes in order to work

[Itxaka]

New framework image should be built to test this with changes to:

• immucore
• sdk
• agent
• packages

[Itxaka]

Welp, seems to work? Wtf.

Okay, cutting new framework and os builder version

[Itxaka]

Now ready to be reviewed finally :D

[Wolverine65]

Hello,

When upgrading within kubernetes from e.g. 22.04-standard-amd64-generic-v3.2.2-k3sv1.30.5-k3s1

the upgrade gives below error and can not be applied

making a symbolic link works as a workaround

ln -s /etc/os-release /etc/kairos-release

`+ HOST_DIR=/host

• '[' '' '!=' true ']'
• '[' -f /etc/kairos-release ']'
  ++ source /etc/kairos-release
  +++ KAIROS_TARGETARCH=amd64
  +++ KAIROS_ID=kairos
  +++ KAIROS_VERSION=v3.2.2-v1.31.1-k3s1
  +++ KAIROS_VERSION_ID=v3.2.2-v1.31.1-k3s1
  +++ KAIROS_PRETTY_NAME='kairos-standard-ubuntu-22.04 v3.2.2-v1.31.1-k3s1'
  +++ KAIROS_IMAGE_LABEL=22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1-k3s1
  +++ KAIROS_FLAVOR_RELEASE=22.04
  +++ KAIROS_MODEL=generic
  +++ KAIROS_RELEASE=v3.2.2
  +++ KAIROS_BUG_REPORT_URL=https://github.com/kairos-io/kairos/issues
  +++ KAIROS_HOME_URL=https://github.com/kairos-io/kairos
  +++ KAIROS_SOFTWARE_VERSION_PREFIX=k3s
  +++ KAIROS_FLAVOR=ubuntu
  +++ KAIROS_REGISTRY_AND_ORG=quay.io/kairos
  +++ KAIROS_SOFTWARE_VERSION=v1.31.1+k3s1
  +++ KAIROS_NAME=kairos-standard-ubuntu-22.04
  +++ KAIROS_ID_LIKE=kairos-standard-ubuntu-22.04
  +++ KAIROS_IMAGE_REPO=quay.io/kairos/ubuntu:22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1-k3s1
  +++ KAIROS_ARTIFACT=kairos-ubuntu-22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1+k3s1
  +++ KAIROS_FAMILY=ubuntu
  +++ KAIROS_VARIANT=standard
  +++ KAIROS_GITHUB_REPO=kairos-io/kairos
  ++ echo v3.2.2-v1.31.1-k3s1
• UPDATE_VERSION=v3.2.2-v1.31.1-k3s1
• '[' -f /etc/kairos-release ']'
  ++ source /host/etc/kairos-release
  /usr/sbin/suc-upgrade: line 13: /host/etc/kairos-release: No such file or directory
• CURRENT_VERSION=
• HOST_DIR=/host
• '[' '' '!=' true ']'
• '[' -f /etc/kairos-release ']'
  ++ source /etc/kairos-release
  +++ KAIROS_TARGETARCH=amd64
  +++ KAIROS_ID=kairos
  +++ KAIROS_VERSION=v3.2.2-v1.31.1-k3s1
  +++ KAIROS_VERSION_ID=v3.2.2-v1.31.1-k3s1
  +++ KAIROS_PRETTY_NAME='kairos-standard-ubuntu-22.04 v3.2.2-v1.31.1-k3s1'
  +++ KAIROS_IMAGE_LABEL=22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1-k3s1
  +++ KAIROS_FLAVOR_RELEASE=22.04
  +++ KAIROS_MODEL=generic
  +++ KAIROS_RELEASE=v3.2.2
  +++ KAIROS_BUG_REPORT_URL=https://github.com/kairos-io/kairos/issues
  +++ KAIROS_HOME_URL=https://github.com/kairos-io/kairos
  +++ KAIROS_SOFTWARE_VERSION_PREFIX=k3s
  +++ KAIROS_FLAVOR=ubuntu
  +++ KAIROS_REGISTRY_AND_ORG=quay.io/kairos
  +++ KAIROS_SOFTWARE_VERSION=v1.31.1+k3s1
  +++ KAIROS_NAME=kairos-standard-ubuntu-22.04
  +++ KAIROS_ID_LIKE=kairos-standard-ubuntu-22.04
  +++ KAIROS_IMAGE_REPO=quay.io/kairos/ubuntu:22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1-k3s1
  +++ KAIROS_ARTIFACT=kairos-ubuntu-22.04-standard-amd64-generic-v3.2.2-k3sv1.31.1+k3s1
  +++ KAIROS_FAMILY=ubuntu
  +++ KAIROS_VARIANT=standard
  +++ KAIROS_GITHUB_REPO=kairos-io/kairos
  ++ echo v3.2.2-v1.31.1-k3s1
• UPDATE_VERSION=v3.2.2-v1.31.1-k3s1
• '[' -f /etc/kairos-release ']'
  ++ source /host/etc/kairos-release
  /usr/sbin/suc-upgrade: line 13: /host/etc/kairos-release: No such file or directory
• CURRENT_VERSION=`

[Itxaka]

@Wolverine65 thanks, opened a ticket on #3010