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DEV_WORKFLOW.md

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+# Developer Workflow
+
+Workflow tiêu chuẩn:
+
+Issue → Branch → Code → Commit → Push → Pull Request → Review → Merge
+
+## Clone repo
+git clone http://gitea.company.com/project/chat-system.git
+cd chat-system
+
+## Pull code
+git checkout main
+git pull origin main
+
+## Tạo branch
+git checkout -b feature/new-feature
+
+## Commit
+git add .
+git commit -m "feat(module): add new feature"
+
+## Push
+git push origin feature/new-feature
+
+## Tạo Pull Request trên Gitea và chờ review.