perf(test): speed up config tests

src/config/env-vars.ts

@@ -29,3 +29,16 @@ export function collectConfigEnvVars(cfg?: OpenClawConfig): Record<string, strin
 
   return entries;
 }
+
+export function applyConfigEnvVars(
+  cfg: OpenClawConfig,
+  env: NodeJS.ProcessEnv = process.env,
+): void {
+  const entries = collectConfigEnvVars(cfg);
+  for (const [key, value] of Object.entries(entries)) {
+    if (env[key]?.trim()) {
+      continue;
+    }
+    env[key] = value;
+  }
+}