Use unsigned diagnostic translation indexes

[Daniiiil1]

Fixes #33.

What changed

• use uint16_t for hardware, updater, key/value lookup indexes in the bridge and updater API
• parse lookup-table indexes with explicit uint16_t range validation instead of signed std::stoi
• replace polynomial map-key comparisons with lexicographic tuple comparisons, avoiding overflow and collisions across the full 16-bit range
• update examples and add boundary coverage for ID 65535
• add the contributor entry required by CONTRIBUTING.md

Why

The ROS messages already encode these translation indexes as unsigned 16-bit values, but the bridge and updater retained signed types. Negative IDs are not valid indexes, and the mismatch could narrow or reinterpret values when moving between the updater, generated messages, and bridge. The polynomial comparator could also overflow for valid 16-bit IDs.

Validation

• git diff --check
• cppcheck --enable=warning,style,performance,portability --std=c++14 --suppress=missingIncludeSystem on the changed bridge C++ files
• cppcheck --enable=warning,style,performance,portability --std=c99 --suppress=missingIncludeSystem on the changed updater C files

The local environment does not include ROS 2/colcon, so the ROS package build and gtests were not run locally. This PR remains a draft pending CI or a maintainer ROS workspace build.