CI: Address occasional ccache install hangs

[padelsbach]

Description

Description

CI can hang until the job timeout when the apt mirror stalls.

• add ccache to ubuntu-22.04-minimal (matches 24.04) and install it from the
  bundle rather than apt
• bound the apt fallback in install-apt-deps with per-command timeouts and a
  retry count -- affects all 51 workflows using it
• fips-dev-no-post opts out (ghcr-debs-tag: none): it pulls the linuxkm
  bundle, so -minimal would be a second, larger download just for ccache

After merge, run ci-deps-image via workflow_dispatch to republish the 22.04
bundle; until then aesgcm-siv and multi-arch fall back to apt (no breakage).

Testing

CI run

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation