test(repo): Prevent Python test bytecode drift

Set PYTHONDONTWRITEBYTECODE for the shared Python runner and the
root test-suite launcher so local test runs do not create __pycache__
artifacts inside skills.

This keeps npm run test deterministic and avoids false negatives in the
editorial bundle inventory checks.

tools/scripts/tests/run-test-suite.js

@@ -58,7 +58,13 @@ function isNetworkTestsEnabled() {
 }
 
 function runNodeCommand(args) {
-  const result = spawnSync(process.execPath, args, { stdio: "inherit" });
+  const result = spawnSync(process.execPath, args, {
+    env: {
+      ...process.env,
+      PYTHONDONTWRITEBYTECODE: process.env.PYTHONDONTWRITEBYTECODE || "1",
+    },
+    stdio: "inherit",
+  });
 
   if (result.error) {
     throw result.error;