Add nlohmann json dependency

[abeltrano]

Type

• Bug fix
• Feature addition
• Feature update
• Documentation
• Build Infrastructure

Side Effects

• Breaking change
• Non-functional change

Goals

• Enable ability to process json.

Technical Details

• Add nlohmann-json vcpkg as a dependency.

Test Results

• Build tested on Linux.

Reviewer Focus

• None

Future Work

• None

Checklist

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