fix(tests): omit env option when no custom env vars provided

The spawn function might be spreading or manipulating the env parameter
internally. By not passing the env option at all when no custom
environment variables are needed, we allow the spawn function to use
process.env directly, preserving Windows proxy behavior.

Only pass env when spawnEnv is provided for custom environment
variables.

Author: jdalton

packages/cli/test/utils.mts

@@ -266,19 +266,22 @@ export async function spawnSocketCli(
   const commandArgs = isJsFile ? [entryPath, ...args] : args
 
   try {
-    // Build env without spreading process.env to preserve Windows proxy behavior.
+    // Build options conditionally to avoid passing env when not needed.
+    // This preserves Windows process.env proxy behavior.
     // Spreading process.env breaks case-insensitive env var access on Windows.
-    const env = spawnEnv ? { ...constants.processEnv, ...spawnEnv } : constants.processEnv
-
-    const output = await spawn(command, commandArgs, {
+    const spawnOptions = {
       cwd,
-      env,
       ...restOptions,
       // Close stdin to prevent tests from hanging
       // when commands wait for input. Must be after restOptions
       // to ensure it's not overridden.
       stdio: restOptions.stdio ?? ['ignore', 'pipe', 'pipe'],
-    })
+      // Only add env if custom environment variables are provided.
+      // This avoids breaking Windows process.env proxy behavior.
+      ...(spawnEnv ? { env: { ...constants.processEnv, ...spawnEnv } } : {}),
+    }
+
+    const output = await spawn(command, commandArgs, spawnOptions)
     return {
       status: true,
       code: 0,