refactor: collapse dual-mode plumbing — the DOM port is the only WASM build

The canvas (wxUniversal) mode is gone (wxwidgets submodule); remove every
piece of side-by-side plumbing so there is exactly one build and one test
flow:

- scripts/build-wxuniversal-wasm.sh -> scripts/build-wx-wasm.sh; no
  --dom/--enable-universal; builds into build-wasm/wxwidgets
- build-wasm-test.sh: no DOM_BUILD / apps-dom rsync mirror / PORT=dom;
  apps build straight into tests/apps (Makefile.wasm PORT conditionals
  collapsed; wx.js + wx-dom.js always pre-js)
- docker/build.sh, build-kicad-target.sh, env.sh: WX_PORT / -dom /
  -universal suffixes removed; kicad builds to kicad-<app>, outputs to
  output/; wx.js/wx-dom.js copied from the real source path
  (/workspace/wxwidgets/build/wasm — the old build-wasm path never
  existed and silently failed)
- setup-kicad-wasm.sh: single target dir; the perl wx-dom.js injection is
  gone — the 7 checked-in kicad pages now reference wx-dom.js directly
- playwright configs serve apps/; fixtures drop the test-results/dom and
  logs/wxwidgets/dom namespacing; boot.spec asserts wxDomPort
  unconditionally; pcbnew.spec uses one reference image;
  appearance.spec assertions unconditional
- compare/update-baseline-screenshots.sh: --port removed
- tests/gal-regression/wasm/Makefile: links build-wasm/wxwidgets and
  carries wx-dom.js as a second pre-js — the gal-webgl suite (30 specs)
  now actually builds and runs here (it needed host-side boost+glm via
  scripts/deps; the bundle had been missing, timing the whole spec out)
- tests: clickCanvas() dispatches via page.mouse (DOM widgets
  legitimately cover the canvas; locator actionability refused the
  click); the comprehensive spec drives wxChoice through its native
  <select> (browser-owned popup cannot be coordinate-clicked)
- docs: README/CLAUDE.md/build.md script names and dirs;
  features/wx-dom-port README reframed (DOM is THE port), visual-notes
  bugs 26-28; FindwxWidgets.cmake config label drops 'wasmuniv'
- wxwidgets submodule -> 9dbacc9448 (DOM-only port, fork diff shrunk)

Gate: full wx e2e suite 292 passed / 1 skipped / 0 failed — first run
ever with the gal-webgl specs green (28 scenarios + load + sequential).

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

scripts/build-wasm-test.sh

@@ -10,7 +10,6 @@ source "$(dirname "$0")/common/env.sh"
 #   ./build-wasm-test.sh              # Incremental build (default)
 #   ./build-wasm-test.sh --clean      # Clean build from scratch
 #   ./build-wasm-test.sh --debug      # Build with debug symbols
-#   ./build-wasm-test.sh --dom        # Build against the DOM port into tests/apps-dom
 #   ./build-wasm-test.sh menu         # Build only the menu test
 #   ./build-wasm-test.sh --debug menu # Build menu test with debug symbols
 
@@ -18,7 +17,6 @@ set -e
 
 DEBUG_BUILD=0
 CLEAN_BUILD=0
-DOM_BUILD=0
 TARGET=""
 
 # Parse arguments
@@ -27,8 +25,6 @@ for arg in "$@"; do
         DEBUG_BUILD=1
     elif [ "$arg" = "--clean" ]; then
         CLEAN_BUILD=1
-    elif [ "$arg" = "--dom" ]; then
-        DOM_BUILD=1
     elif [ "$arg" != "" ]; then
         TARGET="$arg"
     fi
@@ -38,29 +34,8 @@ SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 PROJECT_ROOT="$(dirname "$SCRIPT_DIR")"
 TESTS_DIR="$PROJECT_ROOT/tests"
 
-if [ "$DOM_BUILD" = "1" ]; then
-    BUILD_DIR="$PROJECT_ROOT/build-wasm/wxwidgets-dom"
-    # DOM apps build in a mirrored source tree so canvas and DOM bundles
-    # coexist; relative ../../ paths in Makefile.wasm resolve identically.
-    WASM_APP_DIR="$TESTS_DIR/apps-dom"
-    echo "Mirroring test app sources into apps-dom..."
-    # kicad/ is excluded: apps-dom/kicad is owned by
-    # tests/scripts/setup-kicad-wasm.sh (DOM bundles + injected pages) and
-    # apps/kicad only has the checked-in HTML — mirroring with --delete
-    # would wipe the synced multi-hundred-MB kicad artifacts.
-    rsync -a --delete \
-        --exclude 'kicad/' \
-        --exclude '*.o' --exclude '*.d' \
-        --exclude '*_test.html' --exclude '*_test.js' --exclude '*_test.wasm' \
-        --exclude '*_repro.html' --exclude '*_repro.js' --exclude '*_repro.wasm' \
-        --exclude '*.wasm.map' \
-        "$TESTS_DIR/apps/" "$WASM_APP_DIR/"
-    MAKE_PORT_ARGS="PORT=dom"
-else
-    BUILD_DIR="$PROJECT_ROOT/build-wasm/wxwidgets-universal"
-    WASM_APP_DIR="$TESTS_DIR/apps"
-    MAKE_PORT_ARGS=""
-fi
+BUILD_DIR="$PROJECT_ROOT/build-wasm/wxwidgets"
+WASM_APP_DIR="$TESTS_DIR/apps"
 STANDALONE_DIR="$WASM_APP_DIR/standalone"
 
 echo "=== Building wxWidgets WASM Test Applications ==="
@@ -80,7 +55,7 @@ echo "Test app dir: $WASM_APP_DIR"
 
 # Verify wxWidgets is built
 if [ ! -f "$BUILD_DIR/wx-config" ]; then
-    echo "ERROR: wxWidgets not built. Run build-wxuniversal-wasm.sh first"
+    echo "ERROR: wxWidgets not built. Run build-wx-wasm.sh first"
     exit 1
 fi
 
@@ -120,9 +95,9 @@ fi
 # Build (pass DEBUG flag if requested). App links are independent, so honor
 # JOBS/PARALLEL_JOBS from env.sh (each emcc link is slow due to Asyncify).
 if [ "$DEBUG_BUILD" = "1" ]; then
-    make -j"${JOBS:-1}" -f Makefile.wasm DEBUG=1 $MAKE_PORT_ARGS "$MAKE_TARGET"
+    make -j"${JOBS:-1}" -f Makefile.wasm DEBUG=1 "$MAKE_TARGET"
 else
-    make -j"${JOBS:-1}" -f Makefile.wasm $MAKE_PORT_ARGS "$MAKE_TARGET"
+    make -j"${JOBS:-1}" -f Makefile.wasm "$MAKE_TARGET"
 fi
 
 echo ""