fix: 修复嵌套联合类型合并、非对象根类型生成与 Python 导入顺序

- mergeTypes 扁平化嵌套 union，避免联合成员丢失
- TypeScript/Go/Python 支持数组、标量、联合作为根类型
- TypeScript 数组元素为联合时加括号避免优先级歧义
- Python 在调用 pyTypeName 后根据实际类型补全 typing 导入

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: wangruofeng

index.html

@@ -509,12 +509,19 @@ <h3>粘贴 JSON 文本</h3>
   if (types.length === 0) return scalarType('any');
   if (types.length === 1) return types[0];
 
-  // 分离标量、数组、对象、联合
+  // 先展开嵌套的联合类型
+  const flat = [];
+  function pushType(t) {
+    if (t.kind === 'union') t.types.forEach(pushType);
+    else flat.push(t);
+  }
+  types.forEach(pushType);
+
+  // 分离标量、数组、对象
   const scalars = [];
   const arrays = [];
   const objects = [];
-  for (const t of types) {
-    if (t.kind === 'union') { mergeTypes(t.types); continue; }
+  for (const t of flat) {
     if (t.kind === 'scalar') scalars.push(t);
     else if (t.kind === 'array') arrays.push(t);
     else if (t.kind === 'object') objects.push(t);
@@ -609,7 +616,7 @@ <h3>粘贴 JSON 文本</h3>
     }
     if (t.kind === 'array') {
       const item = tsTypeName(t.item, fallbackName + 'Item');
-      return item + '[]';
+      return (item.includes('|') ? '(' + item + ')' : item) + '[]';
     }
     if (t.kind === 'object') {
       const name = fallbackName;
@@ -645,7 +652,12 @@ <h3>粘贴 JSON 文本</h3>
     return tsTypeName(t, fallbackName);
   }
 
-  tsTypeName(type, rootName);
+  if (type.kind === 'object') {
+    tsTypeName(type, rootName);
+  } else {
+    const rootTypeStr = tsTypeName(type, rootName);
+    defs.push(`type ${rootName} = ${rootTypeStr};`);
+  }
   return defs;
 }
 
@@ -705,7 +717,12 @@ <h3>粘贴 JSON 文本</h3>
 
   defs.push('package main');
   defs.push('');
-  goTypeName(type, rootName, '');
+  if (type.kind === 'object') {
+    goTypeName(type, rootName, '');
+  } else {
+    const rootTypeStr = goTypeName(type, rootName, '');
+    defs.push(`type ${rootName} ${rootTypeStr}`);
+  }
   return defs;
 }
 
@@ -770,15 +787,21 @@ <h3>粘贴 JSON 文本</h3>
     return pyTypeName(t, fallbackName);
   }
 
-  if (needsOptional || needsAny) {
-    const imports = [];
-    if (needsAny) imports.push('Any');
-    if (needsOptional) imports.push('Optional');
-    defs.push(`from typing import ${imports.join(', ')}`);
+  if (type.kind === 'object') {
+    pyTypeName(type, rootName);
+  } else {
+    const rootTypeStr = pyTypeName(type, rootName);
+    defs.push(`${rootName} = ${rootTypeStr}`);
   }
-  defs.push('from dataclasses import dataclass');
-  defs.push('');
-  pyTypeName(type, rootName);
+
+  const imports = [];
+  if (needsAny) imports.push('Any');
+  if (needsOptional) imports.push('Optional');
+  const head = ['from dataclasses import dataclass'];
+  if (imports.length) head.unshift(`from typing import ${imports.join(', ')}`);
+  head.push('');
+  defs.unshift(...head);
+
   return defs;
 }