Make ktem official (#134)

* Move kotaemon and ktem into same folder

* Update docs

* Update CI

* Resolve mypy, isorts

* Re-allow test pdf files

libs/ktem/launch.py

@@ -0,0 +1,5 @@
+from ktem.main import App
+
+app = App()
+demo = app.make()
+demo.queue().launch()