fix(omptype): restored required-first wire ordering and defaulted optional keys

- Restored required-before-optional property ordering in JSON Schema emission; downstream wire consumers (pi-ai toolWireSchema) rely on that stable ordering.
- Mapped Type.Optional with a default to a plain defaulted key in the TypeBox shim, since omptype (like ArkType) rejects optional keys that specify defaults.

packages/omptype/src/json-schema.ts

@@ -273,7 +273,10 @@ function emitObject(
 	const properties: Record<string, unknown> = {};
 	const required: string[] = [];
 	const filled = (prop: PropIR): boolean => !prop.opt && (ctx.options?.io === "output" || !prop.hasDefault);
-	for (const prop of props) {
+	// ArkType emits required properties first (each group in declaration
+	// order); downstream wire consumers rely on that stable ordering.
+	const ordered = [...props.filter(filled), ...props.filter(prop => !filled(prop))];
+	for (const prop of ordered) {
 		if (typeof prop.key === "symbol") throw new TypeError("Cannot convert a symbol to a string");
 		const key = String(prop.key);
 		const propertySchema = emit(prop.val, ctx);

packages/omptype/src/typebox.ts

@@ -401,7 +401,11 @@ function tObject<const P extends Record<string, AnySchema>>(properties: P, opts?
 	for (const key in properties) {
 		const schema = properties[key];
 		const inner = asRuntime<unknown>(schema)[OPTIONAL_INNER];
-		def[inner ? `${key}?` : key] = inner ?? schema;
+		// A defaulted `Type.Optional(...)` maps to a plain defaulted key:
+		// omptype (like ArkType) rejects `key?` with a default, and a default
+		// already makes the key omittable on input.
+		const optionalKey = inner !== undefined && !asRuntime<unknown>(inner).hasDefault;
+		def[optionalKey ? `${key}?` : key] = inner ?? schema;
 		props[key] = schema;
 	}
 	if (opts?.additionalProperties === false) def["+"] = "reject";