[Copilot]

CR-only scripts could fail during indentation inference because parser line numbers were matched against LF-only splits. The formatter also needs to retain CR-only separators throughout edits.

• Line handling: Split on CRLF, CR, or LF, and use the same splitting for indentation inference.
• Regression coverage: Add an in-place formatting test that checks CR-only line endings remain unchanged.

$script = "function foo {`r`t`$x=1`r}"
# Invoke-Formatter preserves the CR-only line endings.

[Copilot]

🟢 Approval recommended

The focused changes consistently handle CR-only lines and include regression coverage, with no unresolved findings.

No open issues 🎉

What changed in this PR

Fixes CR-only line handling so the formatter can infer indentation correctly and preserve those line endings when formatting files.

Changes:

• Recognizes CRLF, CR, and LF separators through the shared line-splitting helper.
• Uses that helper for indentation inference.
• Adds an in-place CR-only regression test and makes the legacy-encoding fixture independent of the test file’s encoding.

File	Description
Tests/​Engine/​InvokeFormatter.tests.ps1	Verifies CR-only formatting output and saved contents; updates the legacy-encoding fixture.
Engine/​Extensions.cs	Splits text on CRLF, CR, or LF.
Engine/​Commands/​InvokeFormatterCommand.cs	Uses shared line splitting for indentation inference.

_{Review effort: Balanced}