Allow workspaces to run project npm tasks

tasks/npm.mjs

@@ -14,7 +14,20 @@ export async function script (name, args = []) {
   const command = process.platform === 'win32' ? 'npm.cmd' : 'npm'
 
   return new Promise((resolve, reject) => {
-    const script = spawn(command, ['run', name, '--silent', ...args])
+    const script = spawn(command, [
+      'run',
+      name,
+
+      // Allow workspaces to run project npm tasks
+      '--if-present',
+      '--include-workspace-root',
+
+      // Prevent duplicate npm output
+      // already logged by Gulp
+      '--silent',
+
+      ...args
+    ])
 
     // Send output to console
     script.stdout.on('data', (data) => console.log(data.toString()))