Lanstzz/sapi-budget

Cost display for AiSpot (sapi) relays: crawls the provider's group list from its public pricing endpoints instead of hardcoding it, lets you pick the active group from a dropdown in the conversation header, and shows a per-turn cost at the end of each turn plus a session total that recurses through every subagent subtree. Switching groups re-prices all history instantly, because the host publishes token buckets only and the browser applies the live rates.