Fixes #39079 - Fix containerfile-install-command when no packages found

[pavanshekar]

The API was changed to return packageCount: 0 with HTTP 200 when no transient packages are found, instead of returning a message with HTTP 404. This caused the command to display nothing and exit with code 0.

This PR adds an execute method override that checks the packageCount field and displays "No transient packages found" with a non-zero exit code when no packages are present.

[vsedmik]

Functionally-wise looks good to me - the test passed detecting the expected result against a packit VM.

2026-02-16 11:37:57 - broker.hosts - DEBUG - sat.redhat.com executing command: LANG=en_US.UTF-8  hammer -v -u admin -p <pass>  host package containerfile-install-command --host-id="2" 
2026-02-16 11:37:57 - broker.hosts - DEBUG - Creating SSH session to sat.redhat.com
2026-02-16 11:37:57 - broker.session - DEBUG - Attempting to load SSH backend: hussh
2026-02-16 11:38:02 - broker.hosts - DEBUG - sat.redhat.com command result:
    stdout:
    
    stderr:
    No transient packages found
    
    status: 128

[chris1984]

ACK, code looks good to ME and tested it

[ianballou]

Works well, thanks!

[vagrant@centos9-hammer-devel hammer-cli-katello]$ hammer host package containerfile-install-command --host-id 13

No transient packages found

[vagrant@centos9-hammer-devel hammer-cli-katello]$ hammer host package containerfile-install-command --host-id 2

RUN dnf install -y acl-2.3.2-4.el10.x86_64