Feat/regenerate answer (#7)

* Add regen button and repharasing question on regen

* Stop appending regen messages to history, allow only one

* Add dynamic conversation state

* Allow reasoning pipeline to manipulate state

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Co-authored-by: albert <albert@cinnamon.is>
Co-authored-by: Duc Nguyen (john) <trungduc1992@gmail.com>

libs/ktem/ktem/app.py

@@ -17,6 +17,7 @@ class BaseApp:
 
     The main application contains app-level information:
         - setting state
+        - dynamic conversation state
         - user id
 
     Also contains registering methods for: