Vanderhell/skipspace ? reverse-engineered prompt

Build me a small, portable C library for embedded systems that can traverse huge implicit search spaces without using the heap.

I want it to keep a compact state for the current path, count how many valid continuations exist from that point with safe saturating arithmetic, and let the caller either visit or skip an entire subtree. It should be deterministic, fixed memory only, and work in plain C with C++ friendly headers, no Arduino or ESP IDF stuff.

Please include a simple public API for push and pop style navigation, subtree counting, can skip checks, and workspace sizing. Add a quickstart example, a few tests, and a basic CMake build so I can compile and run it easily. Keep the core small and focused, since this is meant for embedded use and not a general solver.

If you need to, look up current docs online for any CMake or testing details.