🐛 Fix render-wasm wrapper skipping compilation and copying

./build and pnpm run build:wasm produced no artifacts, dropped extra
Cargo arguments, and watch compiled outside the lock without copying.

Build now runs cargo build and copy_target_artifacts under the
existing lock. Cargo arguments survive as an array, and watch re-entry
no longer duplicates profile flags.
Destinations accept environment overrides so callers can stage
artifacts outside the public paths.

AI-assisted-by: deepseek-flash

render-wasm/build

@@ -46,4 +46,7 @@ else
     test -d node_modules/esbuild || { echo "Run pnpm install in render-wasm before benchmarking" >&2; exit 1; };
 fi
 
+build
+copy_target_artifacts
+
 popd > /dev/null