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Hey! Your PR title Fix GitHub Copilot token exchange and dynamic base URL resolution doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
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• refactor: or refactor(scope): code refactoring
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The following comment was made by an LLM, it may be inaccurate:

Based on my search, I found related PRs that address similar Copilot token handling issues:

1. PR fix(copilot): enable Copilot Business/Enterprise support — bearer exchange, dynamic endpoint, VS Code identity headers #20758 - "fix(copilot): enable Copilot Business/Enterprise support — bearer exchange, dynamic endpoint, VS Code identity headers"

   • Related: Also addresses token exchange and dynamic endpoint resolution for Copilot

2. PR fix(copilot): add token exchange and editor headers for corporate network compatibility #18782 - "fix(copilot): add token exchange and editor headers for corporate network compatibility"

   • Related: Focuses on token exchange and compatibility headers for Copilot

3. PR feat(webfetch): add RFC 9728 auth flow and harden OAuth handling #22096 - "feat(webfetch): add RFC 9728 auth flow and harden OAuth handling"

   • Related: Addresses OAuth flow improvements and token handling

These PRs appear to be addressing similar concerns with Copilot token exchange and OAuth flows, though PR #25995 (your current PR) may be a more recent or focused fix. You may want to review whether these older PRs have been merged or superseded, and ensure your implementation doesn't conflict with or duplicate work from PR #20758 and #18782.

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
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