Add gnaw to non-standard Forth implementations

[warlyjr-cloud]

Adding gnaw under Non-standard Forth implementations, which is where I think it honestly belongs — it borrows Forth's model but makes no claim to the standard (no IMMEDIATE/POSTPONE, no CREATE/DOES>, no vocabularies, and the README says so plainly).

It's a small language in Rust: whitespace-separated words, data stack, : name ... ;, a separate return stack (>r r> r@), if/else/then, begin/until, counted do/loop with i, and a see disassembler. Single-pass compiler (jumps back-patched from a stack of pending holes, no AST) into a bytecode VM.

What makes it not-just-another-toy-Forth is the set of built-in words for byte transforms used in CTF and reverse-engineering work — hex>bytes, xorkey (repeating key), rot13, b64encode/b64decode, brute (all 256 single-byte XOR keys, filtered by a text heuristic), and slurp to pull a real file in. They share one ( addr len -- addr len ) shape so they compose:

"051807040f010d15113c1d153c150a0a02031e" hex>bytes "ctf" xorkey type cr
→ flag{gnaw_is_alive}

There's a WebAssembly playground if it's easier to try than to clone. No hard feelings if you'd rather keep the list to more established implementations.