Have PowerShell formatter remove trailing whitespace when formatting a file

Prerequisites

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Summary

When allowing the PSScriptAnalyzerSettings.psd1 to show Information-level problems, it adds a lot of overhead in formatting files that have lines with trailing whitespaces. Since this recommendation is mostly aesthetic/non-breaking, as is the automated code formatting in general, I'd like to see the formatter for PowerShell remove these trailing whitespaces characters.

https://learn.microsoft.com/en-us/powershell/utility-modules/psscriptanalyzer/rules/avoidtrailingwhitespace?view=ps-modules

Because we can't store a centralized configuration for PSScriptAnalyzerSettings.psd1 in source control at the repo/workspace level to have it be taken automatically be any user working on that repo, having per-user rules to suppress this aren't really practical. I did see a separate thread in this project's issues noting individual users can set a configuration flag to do this, but again, having every user do that themselves vs. having a central linting rule is frustrating to maintain adherence on. Short of having a CI/CD pipeline hard reject any PSScriptAnalyzer errors to force them to check in cleaned code, an automated approach is best.

Proposed Design

No response

The issue does not name a source file or test. Start by locating the PowerShell formatter implementation in this TypeScript VS Code extension and reproduce formatting on a file with trailing whitespace. Done means formatted output removes trailing whitespace without changing unrelated content, with coverage in the relevant formatting tests if they exist.