Add capability-gated router sensors and diagnostics

[fraviktor]

Add gateway, WAN, DSL, and DOCSIS sensors with firmware-aware capability discovery. Improve API session handling and diagnostics,
add English and Hungarian translations,
expand tests and documentation, and provide a privacy-safe router profile collector for contributors.

[iMicknl]

Thanks for the many improvements, @fraviktor! It seems to me that part of the code (e.g. the API implementation and docsis code) should live in the underlying python-sagemcom-api. Would you be willing to move parts of your code there?

[fraviktor]

Thanks for the many improvements, @fraviktor! It seems to me that part of the code (e.g. the API implementation and docsis code) should live in the underlying python-sagemcom-api. Would you be willing to move parts of your code there?

Sure, I can do it, you're completely right about separating the layers. Thanks.

[iMicknl]

Thanks @fraviktor! And if you are able to test iMicknl/python-sagemcom-api#386 and iMicknl/python-sagemcom-api#454, that would be appreciated as well.

I don't have my Sagemcom f@st router where I tested this on anymore, and my other one is in bridge mode currently.