CLI: TableOutput unit tests

[dkbennett]

Summary of the Pull Request

Updates the table class slightly to make it easier for unit testing.
Adds unit tests to verify table output behavior.

PR Checklist

• Closes: Link to issue #xxx
• Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• Tests: Added/updated if needed and all pass
• Localization: All end user facing strings can be localized
• Dev docs: Added/updated if needed
• Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Main change to tableoutput is adding a default output function and the ability to override it. The override is mainly for testing, but it may be useful in other contexts in the future.

Validation Steps Performed

Tests validated and passed

[Copilot]

Pull request overview

This PR makes TableOutput more unit-testable by adding injectable output and a console-width override, and introduces new CLI-focused unit tests to validate table rendering behavior.

Changes:

• Add an overridable output function to TableOutput (defaulting to stdout) to enable in-memory capture in tests.
• Add a console width override to make column-shrinking tests deterministic.
• Add a new unit test suite covering headers, padding, width expansion/truncation, shrinking, and IsEmpty().

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 5 comments.

File	Description
test/windows/wslc/WSLCCLITableOutputUnitTests.cpp	Adds unit tests for TableOutput rendering and sizing behavior using the new output injection hooks.
src/windows/wslc/core/TableOutput.h	Adds SetOutputFunction and SetConsoleWidthOverride, and routes rendered lines through the configured output function.

[benhillis]

Hey @dkbennett 👋 — Following up on this draft PR. CI is green, but there are 6 unresolved review threads that still need to be addressed:

• File header mismatch
• Spacing assertion too weak
• Off-by-one in position calculation
• Missing \
  pos\ guards
• Empty function guard in \SetOutputFunction\
• Suggestion to move to a shared helper

Is this change still being worked on? It's been a few days since the last update. Let us know if you need any help with the review feedback!

[dkbennett]

Hey @dkbennett 👋 — Following up on this draft PR. CI is green, but there are 6 unresolved review threads that still need to be addressed:

• File header mismatch
• Spacing assertion too weak
• Off-by-one in position calculation
• Missing
  pos\ guards
• Empty function guard in \SetOutputFunction\
• Suggestion to move to a shared helper

Is this change still being worked on? It's been a few days since the last update. Let us know if you need any help with the review feedback!

Sorry I got distracted with other things and forgot about this draft PR. I've fixed it up and it is ready.

[Copilot]

Pull request overview

Copilot reviewed 3 out of 3 changed files in this pull request and generated 5 comments.