Restore helper layout in auth, isolation, runtime, and profiles from main

src/isolation.ts

@@ -49,16 +49,6 @@ async function profileProcessIds(uid: number): Promise<number[]> {
     .map(Number);
 }
 
-function killProcess(pid: number): void {
-  try {
-    process.kill(pid, "SIGKILL");
-  } catch (error) {
-    if (!isNotFound(error)) {
-      throw error;
-    }
-  }
-}
-
 // Kills the UID's processes every 10 ms until none is left, for up to 100 rounds.
 export async function killProfileProcesses(uid: number, attempt = 0): Promise<void> {
   if (attempt === 100) {
@@ -69,7 +59,11 @@ export async function killProfileProcesses(uid: number, attempt = 0): Promise<vo
     return;
   }
   for (const pid of ids) {
-    killProcess(pid);
+    try {
+      process.kill(pid, "SIGKILL");
+    } catch (error) {
+      if (!isNotFound(error)) throw error;
+    }
   }
   await sleep(10);
   await killProfileProcesses(uid, attempt + 1);