fix: add plugin config schema helper

src/plugins/config-schema.ts

@@ -0,0 +1,31 @@
+import type { ClawdbotPluginConfigSchema } from "./types.js";
+
+type Issue = { path: Array<string | number>; message: string };
+
+type SafeParseResult =
+  | { success: true; data?: unknown }
+  | { success: false; error: { issues: Issue[] } };
+
+function error(message: string): SafeParseResult {
+  return { success: false, error: { issues: [{ path: [], message }] } };
+}
+
+export function emptyPluginConfigSchema(): ClawdbotPluginConfigSchema {
+  return {
+    safeParse(value: unknown): SafeParseResult {
+      if (value === undefined) return { success: true, data: undefined };
+      if (!value || typeof value !== "object" || Array.isArray(value)) {
+        return error("expected config object");
+      }
+      if (Object.keys(value as Record<string, unknown>).length > 0) {
+        return error("config must be empty");
+      }
+      return { success: true, data: value };
+    },
+    jsonSchema: {
+      type: "object",
+      additionalProperties: false,
+      properties: {},
+    },
+  };
+}