Add initial web editor app, CLI scripts, and test scaffolding.

This introduces the FastAPI editor implementation and related project setup so the app can be run and validated locally.

Made-with: Cursor

code/main.py

@@ -0,0 +1,7 @@
+from time import sleep
+
+i = 0
+while True:
+  print(f"Hello {i}")
+  i += 1
+  sleep(1)