Server/new-api

Аутор	SHA1 Порука	Датум
Seefs	f424f906d8 feat: sync upstream pricing from pricing endpoint (#4452)	пре 2 недеља
CaIon	f2f3410dcf feat: add `len` variable for tier conditions and LLM prompt helper	пре 2 недеља
CaIon	c5405b2a12 feat: add billing expression system documentation and enhance tiered billing logic	пре 1 месец
CaIon	91ed4e196a feat: implement tiered billing expression evaluation and related functionality	пре 1 месец