Fix VT working set and application SonarQube warnings

[sujandumaru]

Describe your changes

This PR reduces SonarQube findings in the Virtual Terminal working-set parser and seeder example while preserving C++11 compatibility.

Changes include:

• Added typed helpers for little-endian decoding and bit operations.
• Replaced repeated casts and manual byte decoding.
• Added explicit conversions to prevent integer precision loss.
• Simplified control flow and removed redundant statements.
• Used single-return implementations where appropriate.
• Improved arithmetic type safety.
• Simplified numeric-value event handling in the seeder example.

Verified SonarQube improvements:

• isobus_virtual_terminal_working_set_base.cpp: 271 → 53 issues
• vt_application.cpp: 10 → 6 issues
• 222 verified issues resolved

The remaining findings generally require broader refactoring and are outside this PR's scope. This work is intended to improve the SonarQube reliability rating from C to A and pass the SonarQube analysis quality gate.

How has this been tested?

The modified files were rescanned using SonarQube for IDE. The project and complete unit-test suite were also run locally:

cmake --build build --target unit_tests
cd build
./test/unit_tests