feat(wasm-dom): Phase 7 plumbing — KiCad DOM-flavor build + test pipeline

WX_PORT=dom flows host → docker container → build scripts:
build-kicad-target.sh selects wxwidgets-dom + kicad-<app>-dom trees;
docker/build.sh passes the env through, copies outputs to output-dom/
incl. wx-dom.js, and post-processes there; build-wxuniversal-wasm.sh
honors WX_PORT and accepts --no-clean again (the kicad pipeline calls it
with that flag — Phase 1's stricter parser had broken the canvas docker
path). setup-kicad-wasm.sh syncs DOM bundles into tests/apps-dom/kicad
and injects the wx-dom.js script tag into the kicad pages;
playwright-kicad.config.ts serves apps-dom under WX_PORT=dom.

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

tests/playwright-kicad.config.ts

@@ -74,6 +74,10 @@ const PCBNEW_FAMILY_SPECS = [
   '**/load-pcb-probe.spec.ts',
 ];
 
+// WX_PORT=dom runs against the DOM-port bundles (setup-kicad-wasm.sh syncs
+// them into tests/apps-dom/kicad).
+const appsDir = process.env.WX_PORT === 'dom' ? 'apps-dom' : 'apps';
+
 export default defineConfig({
   globalSetup: './global-setup.ts',
   testDir: './kicad',
@@ -158,7 +162,7 @@ export default defineConfig({
   ],
 
   webServer: {
-    command: `npx serve apps -p ${port} -c ../serve.json`,
+    command: `npx serve ${appsDir} -p ${port} -c ../serve.json`,
     port: port,
     reuseExistingServer: !process.env.CI,
   },