chore: migrate backend to monorepo apps and biome

biome.json

@@ -0,0 +1,47 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.4.10/schema.json",
+  "files": {
+    "includes": ["**", "!dist", "!coverage", "!node_modules"]
+  },
+  "formatter": {
+    "enabled": true,
+    "indentStyle": "space",
+    "indentWidth": 2,
+    "lineWidth": 100
+  },
+  "assist": {
+    "actions": {
+      "source": {
+        "organizeImports": "on"
+      }
+    }
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true,
+      "style": {
+        "useImportType": "off"
+      }
+    }
+  },
+  "javascript": {
+    "formatter": {
+      "quoteStyle": "single",
+      "trailingCommas": "all"
+    },
+    "parser": {
+      "unsafeParameterDecoratorsEnabled": true
+    },
+    "globals": [
+      "describe",
+      "it",
+      "expect",
+      "beforeEach",
+      "afterEach",
+      "beforeAll",
+      "afterAll",
+      "jest"
+    ]
+  }
+}