handle buildweb condition when its part of a pio chain

scripts/build_interface.py

@@ -110,7 +110,7 @@ def build_webUI(*args, **kwargs):
         env.Exit(1)
     env.Exit(0)            
             
-# Create custom target that only runs the script
+# Create custom target that only runs the script and then exits, without continuing with the pio workflow
 env.AddCustomTarget(
     name="build",
     dependencies=None,
@@ -118,3 +118,10 @@ env.AddCustomTarget(
     title="build web interface",
     description="installs pnpm packages, updates libraries and builds web UI"
 )
+
+# this is if its called with the target=build, so it will continue with the pio workflow
+if not (env.IsCleanTarget()):
+   success = buildWeb()
+   if not success:
+     print("Web interface build failed!")
+