Log message:
devel/yyjson: inital import of package

A high performance JSON library written in ANSI C.

Features:
* Fast: can read or write gigabytes per second JSON data on modern CPUs.
* Portable: complies with ANSI C (C89) for cross-platform compatibility.
* Strict: complies with RFC 8259 JSON standard, ensuring strict number
  format and UTF-8 validation.
* Extendable: offers options to allow comments, trailing commas,
  NaN/Inf, and custom memory allocator.
* Accuracy: can accurately read and write int64, uint64, and double
  numbers.
* Flexible: supports unlimited JSON nesting levels, \u0000 characters,
  and non null-terminated strings.
* Manipulation: supports querying and modifying using JSON Pointer, JSON
  Patch and JSON Merge Patch.
* Developer-Friendly: easy integration with only one h and one c file.