feat: wrap backstage-cli for auth and actions commands

[yangcao77]

Expose auth, actions, and action-source commands on rhdh-cli by passing them through to the bundled backstage-cli binary.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[yangcao77]

@kadel PTAL

[kadel]

Took a closer look at the rebranding in client.ts. There's a small bug where backstage-cli isn't rewritten to rhdh-cli when the name lands across a stream chunk boundary (e.g. one write ends with run backs and the next starts with tage-cli), so the branding occasionally leaks through. It's cosmetic and non-blocking, so no need to hold the PR for it. I've filed RHDHBUGS-3698 to track the fix plus a regression test that splits the name across chunks (the current tests emit output in a single event, so that path isn't exercised yet).

https://issues.redhat.com/browse/RHDHBUGS-3698