Add RadioOperator struct and refactor global variables

[hopeyen]

Description

• Creates a structure RadioOperator to track radio specific logics including radio config, persisted state, radio_msg_handler, control flow (program controller)
  • utilizes MPSC for sending radio message between threads
  • refactors attestation and operations functions, moving the ones accessing global variables to be part of RadioOperator
    • create_radio_message (unused atm, need to decouple from graphcast agent message_send)
    • gossip_poi
    • compare_poi
    • radio_msg_handler
  • Controller not used atm but instead creating and using the Intervals directly in run, due to trouble with control flows
  • Next step is to refactor the ones that make sense to be part of RadioOperator or other new structs; they require more work and time, but might not be the core of this refactor
• Updates Radio config
  • metrics and http services now has the default host of 0.0.0.0
  • adds smart default and getter traits
  • creates and utilizes the refactored CallBook struct with radio specific extension trait
• Updates Persisted state
  • methods to read a snapshot and updating fields underneath Arc Mutex
  • local attestation folded into a Arc std::sync::Mutex with preference to synchronous over async updates, and to be more consistency with remote_messages
• Refactored Http server context for the new Persisted state struct
  • Next we can utilize MPSC for metrics tracking

Issue link (if applicable)

#159

Checklist

• Are tests up-to-date with the new changes?
• Are docs up-to-date with the new changes? (Open PR on docs repo if necessary)