docs(readme): sync Vietnamese ecosystem section with web client link

docs(readme): add ecosystem section with web client repository

Revert "fix(swagger): show topbar and enable explorer input"

fix(swagger): show topbar and enable explorer input

revert(swagger): restore previous swagger-ui configuration

fix(swagger): simplify config and enable explorer input for manual spec URL

fix(swagger): set default url to avoid empty spec screen

docs(swagger): enable server selector and keep topbar visible

docs(swagger): document meal and focus fields in chat session history

feat(chat): include meal items and focus in v1 session history response

docs(chat): clarify recommended vs deprecated chat endpoints for latest clients

docs(chat): add dedicated JWT chat flow API integration guide

docs(readme): rewrite EN and VI README for open-source clarity

docs(jwt): expand v2 API guide with full flows and business codes

chore(docs): remove outdated duplicate API/chat guides