[Bug]: `container system logs --last` accepts invalid time units

[realrajaryan]

I have done the following

• I have searched the existing issues
• If possible, I've reproduced the issue using the 'main' branch of this project

Steps to reproduce

Pass a --last value with an unsupported unit:

$ container system logs --last 1x
Timestamp                       Thread     Type        Activity             PID    TTL

$ echo $?
0

Problem description

Help documents --last as supporting m, h, and d. Invalid values such as 1x should fail before invoking the platform log command. Returning success with only the header makes a bad filter look like an empty log result.

Environment

- OS: macOS 26.4.1 (25E253)
- Xcode: Xcode 26.4.1 (17E202)
- Container: container CLI 0.12.3 (build: release, commit: f989901)

Code of Conduct

• I agree to follow this project's Code of Conduct