refactor: convert to Cargo workspace structure

.dockerignore

@@ -0,0 +1,45 @@
+# Git
+.git
+.gitignore
+.github
+
+# Rust
+target/
+**/*.rs.bk
+
+# Node.js
+node_modules/
+npm-debug.log*
+yarn-debug.log*
+yarn-error.log*
+pnpm-debug.log*
+.pnpm-store/
+
+# Frontend build output
+frontend/dist/
+frontend/.next/
+frontend/out/
+
+# Environment files
+.env
+.env.*
+!.env.example
+
+# IDEs
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.DS_Store
+
+# Documentation
+*.md
+!README.md
+
+# CI/CD
+.github/
+
+# Other
+Justfile
+.dockerignore