fix(schema): use Zod native JSON schema output

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

script/build-schema-document.ts

@@ -1,17 +1,14 @@
-import { zodToJsonSchema } from "zod-to-json-schema"
+import { z } from "zod"
 import { OhMyOpenCodeConfigSchema } from "../src/config/schema"
 
 export function createOhMyOpenCodeJsonSchema(): Record<string, unknown> {
-  const jsonSchema = zodToJsonSchema(OhMyOpenCodeConfigSchema, {
-    target: "jsonSchema7",
-    $refStrategy: "none",
-  })
+  const jsonSchema = z.toJSONSchema(OhMyOpenCodeConfigSchema)
 
   return {
+    ...jsonSchema,
     $schema: "http://json-schema.org/draft-07/schema#",
     $id: "https://raw.githubusercontent.com/code-yeongyu/oh-my-openagent/dev/assets/oh-my-opencode.schema.json",
     title: "Oh My OpenCode Configuration",
     description: "Configuration schema for oh-my-opencode plugin",
-    ...jsonSchema,
   }
 }