Replace ESLint with Biome for linting and formatting, update TypeScript configuration to target ESNext, and refactor code to use type imports. Add new biome.json configuration file and adjust test cases for error handling.

biome.json

@@ -0,0 +1,44 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.2.4/schema.json",
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true
+  },
+  "files": {
+    "ignoreUnknown": false,
+    "includes": ["src/**/*.ts", "test/**/*.ts"]
+  },
+  "formatter": {
+    "enabled": true,
+    "formatWithErrors": false,
+    "indentStyle": "space",
+    "indentWidth": 2,
+    "lineWidth": 100,
+    "lineEnding": "lf"
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true,
+      "correctness": {
+        "noUnusedVariables": "off",
+        "noUnusedFunctionParameters": "off"
+      },
+      "style": {
+        "useConst": "error"
+      },
+      "suspicious": {
+        "noConsole": "warn",
+        "noVar": "error"
+      }
+    }
+  },
+  "javascript": {
+    "formatter": {
+      "quoteStyle": "double",
+      "semicolons": "always",
+      "trailingCommas": "es5"
+    }
+  }
+}