feat: Cleaning up technical debts

[coder11]

Closes: DXJ-328, DXJ-219, DXJ-148

[linear]

DXJ-328 Make max number of streams configurable

See this: https://fluencelabs.slack.com/archives/C8FDH536W/p1677833893040599

And also search for TODO comment in JS Client repo

DXJ-219 Fix hanging jest test for ephemeral networks

DXJ-148 Improve wording and add explanations in error `'No handler has been registered for serviceId ...'`

Right now, error states something like

Local service error, ret_code is 1, error message is '"No handler has been registered for serviceId='onboardingservice' fnName='get_location_game'

One user righteously asked:

what does it mean by handler?

And it is a great question because that word "handler" we do not use anywhere.

This error should be reworded, and explanations on possible solutions/investigations given.