Add more explanatory logging

[alfonsorosd]

Summary

This PR adds explanatory vSomeIP logs to make SOME/IP and SOME/IP-SD debugging easier without changing behavior or configuration.

The focus is the event-driven v1 scope from the issue discussion: log what vSomeIP already knows at the point where it accepts, ignores, acknowledges, rejects, or receives something, instead of introducing new persistent state.

What Changed

• Added SD ingress logs for received service discovery traffic, including sender and whether it arrived via multicast or unicast.
• Expanded SD offer logs so accepted offers and ignored offers include the concrete reason and endpoint context.
• Added subscription lifecycle logs for:
  • SD subscribe send
  • SD unsubscribe send
  • remote subscribe receive
  • remote unsubscribe receive
  • subscribe ACK
  • subscribe NACK
• Added application-side availability transition logs, including when subscription state is reset because a service became unavailable.
• Added debug logs for incoming remote SOME/IP responses and errors with source IP, port, and transport.

Why

This is meant to answer the common debugging questions from the issue more directly, for example:

• whether discovery traffic is received at all
• why an offer was accepted or ignored
• when a subscribe or unsubscribe was sent
• whether a subscription was acknowledged or rejected
• why notifications are later treated as inactive
• from which remote endpoint a response was received

Scope / Non-Goals

• No public API changes
• No new logging configuration flags
• No behavior changes in routing, SD, subscription handling, or availability handling
• No new persistent subscription-state model
• Request timeout diagnostics are not added in this PR

Verification

• git diff --check
• Focused compile of the edited translation units:
  • implementation/service_discovery/src/service_discovery_impl.cpp.o
  • implementation/routing/src/routing_manager_impl.cpp.o
  • implementation/routing/src/routing_manager_client.cpp.o
  • implementation/runtime/src/application_impl.cpp.o