Plugin Wasm Binary Warning

<!-- Canonical warning about committing WASM artifacts. Edit here; reuse via {{#include}}. -->

[!IMPORTANT] Compiled .wasm and .cwasm files are binary artifacts, often megabytes each. Do not check them into a git source tree without Git LFS: every rebuild committed as a plain blob bloats the repository history permanently, and git diff/review tooling chokes on them. Treat them like any other build output: add target/ and *.wasm/*.cwasm to .gitignore, and distribute through a release artifact or plugin registry archive instead. If an artifact truly must live in the tree, track the pattern with LFS (git lfs track "*.wasm") before the first commit.