fix(wasm-dom): serve:dom script; keep kicad bundles out of the apps-dom mirror

The wx test-app mirror (build-wasm-test.sh --dom, rsync --delete) wiped
the kicad bundles setup-kicad-wasm.sh syncs into apps-dom/kicad —
apps/kicad only carries the checked-in HTML. Exclude kicad/ (that dir is
owned by the setup script). Add 'npm run serve:dom' for browsing the
DOM-port apps; plain 'npm run serve' serves the canvas dir, which has no
kicad bundles in this worktree (canvas KiCad was never built here).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

scripts/build-wasm-test.sh

@@ -44,7 +44,12 @@ if [ "$DOM_BUILD" = "1" ]; then
     # coexist; relative ../../ paths in Makefile.wasm resolve identically.
     WASM_APP_DIR="$TESTS_DIR/apps-dom"
     echo "Mirroring test app sources into apps-dom..."
+    # kicad/ is excluded: apps-dom/kicad is owned by
+    # tests/scripts/setup-kicad-wasm.sh (DOM bundles + injected pages) and
+    # apps/kicad only has the checked-in HTML — mirroring with --delete
+    # would wipe the synced multi-hundred-MB kicad artifacts.
     rsync -a --delete \
+        --exclude 'kicad/' \
         --exclude '*.o' --exclude '*.d' \
         --exclude '*_test.html' --exclude '*_test.js' --exclude '*_test.wasm' \
         --exclude '*_repro.html' --exclude '*_repro.js' --exclude '*_repro.wasm' \