Set spend budgets on agent endpoints from the Integrations tab

Sessions now record the endpoint they arrived through, and budgets can target an agent endpoint. Existing App budgets were converted to one budget per endpoint with the same limit and balance.

In the UI: with the app_budgets feature flag on, the agent’s Integrations tab manages agent and endpoint budgets, showing the period, its UTC reset and any refusal. Members without budget.manage see them read-only.

Slack and FCP endpoint budgets now bind and are enforced. If you configured one before and it never took effect, it starts limiting spend.

See Budgets and Enforce a budget. #3719, #3623, #3625