test: migrate from Jest to Vitest

.gitignore

@@ -4,3 +4,4 @@ package-lock.json
 /.idea
 .kiro/coverage/
 coverage/
+nul

CLAUDE.md

@@ -9,8 +9,8 @@ A TypeScript API library (`@ghosttypes/ff-api`) for controlling FlashForge 3D pr
 ## Build & Test Commands
 
 - **Build:** `pnpm build` (runs `tsc`, outputs to `dist/`)
-- **Test all:** `pnpm test` (Jest with ts-jest)
-- **Test single file:** `pnpm exec jest path/to/file.test.ts`
+- **Test all:** `pnpm test` (Vitest)
+- **Test single file:** `pnpm exec vitest run path/to/file.test.ts`
 - **Test watch:** `pnpm test:watch`
 - **Test coverage:** `pnpm test:coverage`
 

biome.json

@@ -0,0 +1,91 @@
+{
+  "$schema": "https://biomejs.dev/schemas/2.3.14/schema.json",
+  "vcs": {
+    "enabled": true,
+    "clientKind": "git",
+    "useIgnoreFile": true
+  },
+  "files": {
+    "ignoreUnknown": false
+  },
+  "formatter": {
+    "enabled": true,
+    "formatWithErrors": false,
+    "indentStyle": "space",
+    "indentWidth": 2,
+    "lineEnding": "lf",
+    "lineWidth": 100
+  },
+  "linter": {
+    "enabled": true,
+    "rules": {
+      "recommended": true,
+      "a11y": {
+        "recommended": true
+      },
+      "correctness": {
+        "recommended": true,
+        "noUnusedVariables": "error",
+        "noUnusedImports": "error"
+      },
+      "complexity": {
+        "recommended": true,
+        "noForEach": "off",
+        "useLiteralKeys": "off",
+        "noStaticOnlyClass": "off"
+      },
+      "style": {
+        "recommended": true,
+        "noParameterAssign": "off",
+        "useConst": "error",
+        "useTemplate": "warn",
+        "noNonNullAssertion": "warn"
+      },
+      "suspicious": {
+        "recommended": true,
+        "noArrayIndexKey": "warn",
+        "noExplicitAny": "warn",
+        "noEmptyBlockStatements": "warn",
+        "noImplicitAnyLet": "warn"
+      },
+      "performance": {
+        "recommended": true
+      },
+      "security": {
+        "recommended": true
+      }
+    }
+  },
+  "javascript": {
+    "formatter": {
+      "quoteStyle": "single",
+      "jsxQuoteStyle": "double",
+      "quoteProperties": "asNeeded",
+      "trailingCommas": "es5",
+      "semicolons": "always",
+      "arrowParentheses": "always",
+      "bracketSpacing": true,
+      "bracketSameLine": false
+    }
+  },
+  "json": {
+    "formatter": {
+      "enabled": true,
+      "indentStyle": "space",
+      "indentWidth": 2,
+      "lineWidth": 100
+    }
+  },
+  "overrides": [
+    {
+      "includes": ["*.test.ts", "**/*.test.ts"],
+      "linter": {
+        "rules": {
+          "suspicious": {
+            "noExplicitAny": "off"
+          }
+        }
+      }
+    }
+  ]
+}