- make stream fast path honor adaptive soft payload limits end-to-end
- split oversized fast-stream payloads into sequential frames before batching
- use adaptive soft cap when encoding stream batch payloads
- move timeout-like error detection into production code for adaptive tx
- tune notify FrameReader read size explicitly to avoid throughput regression
- drop local stario replace and depend on released b612.me/stario v0.1.1
