Fix portable ps command for remote process picker

[HuzaifaAbdulRehman]

Summary

Fixes #14442.

The Linux remote process picker now passes each output column to ps with a separate -o option. This avoids the personality-dependent interpretation of comma-separated format specifications while preserving the existing PID, command name, and arguments output layout.

A regression test verifies the portable command construction, and the changelog documents the fix.

Validation

• corepack yarn compile (passed)
• Targeted ESLint for the changed TypeScript files (passed)
• git diff --check (passed)
• Executed the new command under Ubuntu/WSL and confirmed it produces the expected fixed-width PID, command, and arguments columns

The SingleRootProject scenario runner could not execute locally because the native cpptools binaries are not included in the public source checkout. The scenario test containing the new assertion compiled successfully.

[HuzaifaAbdulRehman]

@microsoft-github-policy-service agree

[HuzaifaAbdulRehman]

@bobbrow The Linux and Windows checks are failing during dependency installation because the Azure package registry returns HTTP 503 responses (for mkdirp and each-props respectively). The macOS check passed, and neither failing job reached the build or the changed code. I attempted to rerun the failed workflows, but GitHub requires repository admin access. Could you please rerun them when convenient?