Update README.md

Author: AntonAzer

README.md

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 # CVCraft Pro — Backend
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+**[![Quality gate](https://sonarcloud.io/api/project_badges/quality_gate?project=AntonAzer_cvbackend)](https://sonarcloud.io/summary/new_code?id=AntonAzer_cvbackend)**
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 ## Front-End Repo is [CVCraft-Pro](https://github.com/AntonAzer/CVCraft-Pro)
 Node.js/Express API backed by Supabase Postgres. Replaces the old front-end-only
 `localStorage` "database" and fake auth with real hashed-password auth (JWT +