The keep-or-lower check compares against the budget update_team read, so the write now only lands while the stored max_budget still matches it and answers 409 otherwise. A concurrent proxy admin cut can no longer be overwritten with a higher value.
The keep-or-lower budget rule only ran for standalone teams, so once max_budget is enabled a team admin on an org team could grow its own budget up to the organization's. It now applies to team admins on every team; org admins keep editing within the org cap.
Adds both fields to the team admin editable allow-list and the dashboard's team admin form. The existing budget authority check still stops a team admin from raising or removing a standalone team's budget.
Team admins are refused until a proxy admin enables a field, then limited to the enabled fields, and resending unchanged budget settings keeps the team's budget reset times
