phsl / new-api

Changes
1. ModelPricingTable.jsx
   • Compute `autoChain` as the intersection of `autoGroups` and the model’s `enable_groups` (order preserved).
   • Display the chain banner only when `autoChain.length > 0`; banner shows the reduced path (e.g. `a → c → e`).
   • Dropped obsolete `selectedGroup` prop; all callers updated.

2. ModelDetailSideSheet.jsx / PricingPage.jsx
   • Removed forwarding of deleted `selectedGroup` prop.

Outcome
– “Auto group routing” appears only for models that actually participate in the chain, avoiding empty or irrelevant banners.
– Codebase simplified by eliminating an unused prop.