Support multiple UwbConnector event registrations

[abeltrano]

Type

• Bug fix
• Feature addition
• Feature update
• Breaking change
• Non-functional change
• Documentation
• Infrastructure

Goals

Allow multiple event consumers to register with UwbConnector.

Technical Details

• Convert the members storing callbacks to store containers (std::vector) instead of individual elements.
• Add helper functions to produce a copy of event callbacks, erasing any that are found to be expired in the process.

Test Results

• Ran end-to-end ranging test, enabled+disabled random measurements on session, observed all events in nocli output.

Reviewer Focus

None

Future Work

This paves the way to allow a single UbwConnector to be used for both UwbDevice and its child UwbSession objects.

Checklist

• Build target all compiles cleanly.
• clang-format and clang-tidy deltas produced no new output.
• Newly added functions include doxygen-style comment block.