PR Summary

*System.Management.Automation/engine/CommandCompletion/CompletionCompleters:
Use WildcardPattern::Escape to escape completion text of filename.

*System.Management.Automation/engine/SessionStateContainer:
@Get-ChildItem
Unescape non-literal, non-glob path before existence checking.
This solve the issue where Get-GhildItem does not behave correctly
when -Path contains special characters. For example,

Get-ChildItem -Path './`[dir`]'

will complain with error "Cannot find path ..." while

Get-ChildItem -Path './`[dir`]' -Depth 0

will work fine.

@New-Item
Unescape non-literal path when -Name is not set.
This works around for New-Item treating -Path as literal path while
it can also be globbable. For example, assuming there is "[file]1"
in current directory, and tab completion suggests './`[file`]1'
for the -Path argument, but

New-Item -Path './`[file`]2'

will create a file named "`[file`]2" instead of "[file]2".

*System.Management.Automation/engine/regex:
WildcardPattern::Escape should also escape "`" since
WildcardPattern::Unescape would unescape it,
and the matcher parse it as escape character.

*System.Management.Automation/namespaces/LocationGlobber:
Do not escape CWD when LiteralPath is used. This causes issues when
both -LiteralPath and CWD contains special characters.
Do not pass regex escaped string to WildcardPattern::Get. This fails
tab completion when doing "./path/to/`[f"<TAB>.

*System.Management.Automation/utils/PathUtils:
Unescape non-literal, non-glob path before calling
GetUnresolvedProviderPathFromPSPath since it only accepts literal path.
This solve the issue where some commands depending on that method
will treat -Path as literal unintentionally. For example,

Out-File -Path './`[out`].txt' -Append

will create a new file named "`[out`].txt" instead of writing to "[out].txt".

PR Checklist

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• Change is not breaking
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• User-facing changes
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• Testing - New and feature
  • Not Applicable or can only be tested interactively
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  • Make sure you've added a new test if existing tests do not effectively test the code changed
    • Add [feature] if the change is significant or affects feature tests