Fix for different per-monitor scaling (#657)

* Use DPIAware::DEFAULT_DPI

* Make runner DPI-unaware, since it doesn't need to use a Per Monitor V2 DPI.

* Programmatically enable "Per Monitor V2 DPI" for the runner proccess and use a separate DPI-unaware thread for the corresponding API calls

* Increase PCH memory limit for settings project

* Address review issues

* Draw zoneWindows properly scaled

src/common/on_thread_executor.h

@@ -0,0 +1,30 @@
+#pragma once
+
+#include <future>
+#include <thread>
+#include <functional>
+#include <queue>
+#include <atomic>
+
+// OnThreadExecutor allows its caller to off-load some work to a persistently running background thread.
+// This might come in handy if you use the API which sets thread-wide global state and the state needs
+// to be isolated.
+
+class OnThreadExecutor final {
+public:
+  using task_t = std::packaged_task<void()>;
+
+  OnThreadExecutor();
+  ~OnThreadExecutor();
+  std::future<void> submit(task_t task);
+
+private:
+  void worker_thread();
+
+  std::thread _worker_thread;
+
+  std::mutex _task_mutex;
+  std::condition_variable _task_cv;
+  std::atomic_bool _active;
+  std::queue<std::packaged_task<void()>> _task_queue;
+};