Remove the 'all-priority-classes' flag from armadactl commands

[JamesMurkin]

For cancel/preempt queue/node/executor, we now simply default to all priority classes unless a priority class filter is provided

The 'all-priority-classes' was cumbersome and users typically always wanted 'all-priority-classes'

Making it default aligns the command with user expectation and makes it easier to use, while keeping the optional filter of priority classes if users need it

I've also reworked the tests - so we don't override RunE etc and let that use the real production code

• This means the tests now run the actual production code and just assert the outputs, which I think is much more robust

[greptile-apps]

Greptile Summary

The PR removes the all-priority-classes flag from cancel and preempt commands and treats an omitted priority-class filter as selecting every class.

• Updates executor, node, and queue command defaults and help text.
• Injects the application dependency into command constructors to support production-path testing.
• Reworks tests to execute real command handlers through API argument construction while faking only external API calls.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
cmd/armadactl/cmd/cancel.go	Removes the explicit all-priority-classes flag and defaults empty priority-class selections to all classes for cancellation commands.
cmd/armadactl/cmd/cancel_test.go	Exercises real cancellation command handlers and verifies their arguments at the API boundary.
cmd/armadactl/cmd/preempt.go	Applies the same default-all priority-class behavior and injectable command construction to preemption commands.
cmd/armadactl/cmd/preempt_test.go	Adds shared API-boundary fakes and verifies real preemption command parsing and request construction.

_{Reviews (2): Last reviewed commit: "More robust tests" | Re-trigger Greptile}

[mergify]

Tick the box to add this pull request to the merge queue (same as @mergifyio queue).

• Queue this pull request