fix(wasm): KiCad 10 kiplatform/libgit2 stubs, e2e fixtures, asyncify -g hook

- wasm/kiplatform: add EnableDarkMode, IO::TimestampDir, UI::AllowNetworkFileSystems,
  UI::CancelPendingScroll, SECRETS::DeleteSecret (new KiCad 10 functions).
- wasm/stubs/libgit2_stub.c: ~156 no-op stubs for KiCad 10's restructured git
  backend + git-backed local history + text_eval VCS.
- tests/kicad: bump the demo project dir 9.99 -> 10.0 (KiCad 10 stores projects
  under /home/kicad/documents/kicad/10.0/) — fixes load-pcb + 3d-viewer e2e.
- scripts/common/apply-asyncify.sh: ASYNCIFY_EXTRA_OPTS hook (e.g. -g for
  symbolizable wasm traces).
- kicad submodule -> ef00c2d3 (KiCad 10 link + runtime adaptations).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

scripts/common/apply-asyncify.sh

@@ -112,7 +112,7 @@ echo "This may take several minutes and use significant RAM..."
 echo "  BINARYEN_CORES=${BINARYEN_CORES}"
 echo "  LD_PRELOAD=${WASM_OPT_PRELOAD:-<none>}"
 
-"${PRELOAD_CMD[@]}" "${TIME_CMD[@]}" "${WASM_OPT}" --asyncify \
+"${PRELOAD_CMD[@]}" "${TIME_CMD[@]}" "${WASM_OPT}" --asyncify ${ASYNCIFY_EXTRA_OPTS:-} \
     "--pass-arg=asyncify-imports@${ASYNCIFY_IMPORTS}" \
     "--pass-arg=asyncify-removelist@${ASYNCIFY_REMOVE_ARG}" \
     --pass-arg=asyncify-propagate-addlist \