Support images in agent2 threads (#36152)

- Support adding ImageContent to messages through copy/paste and through
path completions
- Ensure images are fully converted to LanguageModelImageContent before
sending them to the model
- Update ACP crate to v0.0.24 to enable passing image paths through the
protocol

Release Notes:

- N/A

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Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>
b1e806442aCole Miller committed on 8/14/2025, 9:31:14 PM· committed by GitHubparente2ce787
7 files changedLine totals unavailable