Application layer `libcyphal::application::Node` and its `HeartbeatProducer` & `GetInfoProvider` sub-components.

[serges147]

• Implemented application layer Node class.
• Temporary switch to the specific Nunavut commit, where I've made necessary fixes (see https://github.com/OpenCyphal/nunavut/pull/346)
  • switch to "pmr" flavor of Nunavut c++ code generation
  • modify libcyphal to pass now required pmr allocator to ctor-s of Nunavut generated messages/requests/responses
• Added new application layer example: "example_2_application_0_node_hb_getinfo_udp" - demonstrates how to make a simple libcyphal node using application layer Node class.
• Addressed some todos
• A bit more docs

[sonarcloud[bot]]

Quality Gate passed

Issues
2 New issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud