refactor: prune test-only seams and obsolete helpers (#10275)

src/application/ClientConfigurationFiles.ts

@@ -23,14 +23,14 @@ export interface ClientConfigurationSource extends ClientConfigurationDocument {
 const invalidEnvironment = (
   path: string,
   error: ConfigurationError,
-  overrides: Readonly<Record<string, string>> = {},
-  platform: NodeJS.Platform = process.platform,
+  overrides: Readonly<Record<string, string>> | undefined,
+  platform: NodeJS.Platform,
 ): ClientConfigurationFileError => {
   const constraints = error.settings
     .map(({ setting, constraint }) => `${setting}: ${constraint}`)
     .join("; ");
   const overrideNames = new Set(
-    Object.keys(overrides).map((name) =>
+    Object.keys(overrides ?? {}).map((name) =>
       platform === "win32" ? name.toUpperCase() : name,
     ),
   );