Backend refactor for streaming endpoints (#444)
* wip: complete refactor of streaming backend
* working refactoring
* fix missing first token & perf regression in output quality
* lint
* Fix websearch loading from db
* fix loading
* fix invalidate
* remove logs
* fix SSR error
* typo: paragraphs
* fixed save on abort
* lint
* lint
* remove debug log in console
* lint for real
