fix(ast_tools): run dprint twice

[overlookmotel]

dprint appears to be buggy, and in some cases requires 2 passes to reach a stable state. So run it twice.

This problem discovered in: #14637 (comment)

[overlookmotel]

• fix(ast_tools): run dprint twice #14723 👈 (View in Graphite)
• main

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[Copilot]

Pull Request Overview

This PR addresses a bug in dprint where it requires two formatting passes to reach a stable output state. The changes refactor the format function to run dprint twice consecutively and improve error handling by separating the formatting logic into a dedicated dprint helper function.

Key Changes:

• Run dprint twice to ensure stable formatting output
• Extract dprint execution logic into a separate helper function that returns Result<Vec<u8>, String>
• Improve error handling by consolidating error reporting in the main format function

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[overlookmotel]

Running dprint twice has a cost, so we'll only merge this if we decide to go forwards with #14637. This problem only seems to occur in some rare cases.

[overlookmotel]

We found a different workaround in #14637, so this is no longer needed.