fix #2841 by adding dynamic options

[netwdev]

Since no one liked the idea of saving the server config to a file as in #5153, I decided to try getting all the optional arguments from the client using the first connected socket. The required/important arguments, in contrast, are still given on the command line just like before, but should no longer exceed the character limit of 255.

As of now, the command-line-only arguments are:

• (version)
• log_level
• scid
• tunnel_forward
• control
• video
• audio
• send_dummy_byte (+raw_stream)
• net_args (new)

The optional arguments are received once after the dummy byte is sent (if enabled) and are expected as 4-byte length-prefixed JSON data.

I'm sure there are better ways to do this, but I think this approach might be acceptable because:

• it doesn’t affect scrcpy clients on new releases due to the command-line argument handling
• it has minimal latency impact when enabled

Some drawbacks are:

• two separate argument handling paths are needed
• it introduces a completely new protocol

Closes #2841
Closes #5153

EDIT
I forgot all the "list_*" arguments like "list_encoders" but imo they should be used separately.