- There is not need to use stream management with component, so we set mode to `client`
only.
- `_disconnecting_trigger` was causing an exception when disconnecting a component, it is
now disabled in this case.
This is a huge configuration refactoring.
The configuration system now uses Pydantic settings, with better validation, better
support for environment variables and other goodies.
The main config files now use TOML instead of INI, this allow for better handling of
complex types, notably dict.
Plugins, components and frontends can declare their config settings in a class which will
be imported dynamically.