Rework config values and add settings GUI

[Leidtier]

based on #205 (so maybe integrate this into the base PR first or merge this PR instead) solves #235

Rework config values

• complete rework of how config values work in MantellaSoftware
• All config values are now defined in code, including:
  • ID
  • Name
  • Description
  • Value
  • Default Value
  • Constraints
  • IsHidden
  • Tags
  • OnValueChangeCallback
• On start of the software an instance that holds the current value of each config value is generated from the definitions
• These instances are filled gracefully by which config values can be loaded from the config.ini
• If there is no config.ini a new one will be created from scratch
• ConfigLoader loads the config values now from the current values. Any config value that is actually loaded can trigger a constraint violation
• Any unsolved constraint violations will block the Mantella HTTP routes for conversation or STT from being used until resolved
• A restart of MantellaSoftware is no longer required when changing config values from the GUI

Add settings GUI

• Adds a browser based GUI to MantellaSoftware that uses Gradio
• Changes the Flask server to FastAPI/uvicorn to support serving the new HTTP routes for Mantella as well as the Gradio GUI from the same app
  • No explicit test done, but the responses feel faster than with Flask