Activate thin snapshot after creation with lvchange -K -ay

[guifranchi]

Summary

• Thin LV snapshots are created with the "skip activation" flag (k) set by default on the LVM version running on ci-hel3 (Ubuntu 22.04)
• lvchange -ay silently respects that flag and does nothing — no DM device is ever created, /dev/<vg>/<lv> never appears, and mount fails with ENOENT (exit 32)
• Adds lvchange -K -ay (--ignoreactivationskip) immediately after lvcreate -s, followed by udevadm settle to ensure the /dev symlink is present before returning

Manually confirmed on ci-hel3:

# lvchange -K -ay runners/rootfs-default-0
# ls -la /dev/runners/rootfs-default-0
lrwxrwxrwx 1 root root 7 ... /dev/runners/rootfs-default-0 -> ../dm-5
# mount /dev/runners/rootfs-default-0 /tmp/test-mnt && echo "MOUNT OK"
MOUNT OK

Test plan

• Review and merge
• Create release v0.1.8
• Bump ci_actions_runner_manager_version to 0.1.8 in ansible and deploy to ci-hel3
• Confirm boot cycles progress past the mount step and Firecracker VMs start

🤖 Generated with Claude Code

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