ep: Add the predicted kept characters metric [WIP] (#50566)

Release Notes:

- N/A

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Co-authored-by: Ben Kunkle <ben@zed.dev>
b05a2404efOleksiy Syvokon committed on 4/1/2026, 11:31:21 PM· committed by GitHubparentbbde01a
9 files changedLine totals unavailable