Feature: Expose G14Manager functions via gRPC over localhost TCP for integrations

[zllovesuki]

@aredden expresses interests for integrating electron-G14Control's GUI with G14Manager.

High level abstract:

• electron-G14Control: responsible for exposing an GUI interface for user to view/set configurations
• G14Manager: responsible for setting system states (e.g. Thermal Profile, ROG Key Remap, etc) and returning current system states (e.g. Current Thermal Profile, current charge limit, etc).

This issue tracks the integration proposal and discussions, and implementation changes needed for MVP integration.

Potentially fixes:
#20
#35

[zllovesuki]

#59 should allow for easier loading/saving configurations via Registry

[zllovesuki]

The server side of things are now up and running: https://github.com/zllovesuki/G14Manager/tree/grpc

A client is needed to configure various settings.