common: refactor common library pt2 (#8588)

- remove common lib
- split settings, remove common-md
- move ipc interop/kb_layout to interop
- rename core -> settings, settings -> old_settings
- os-detect header-only; interop -> PowerToysInterop
- split notifications, move single-use headers where they're used
- winstore lib
- rename com utils
- rename Updating and Telemetry projects
- rename core -> settings-ui and remove examples folder
- rename settings-ui folder + consisent common/version include

src/modules/fancyzones/lib/on_thread_executor.h

@@ -0,0 +1,31 @@
+#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);
+    void cancel();
+
+private:
+    void worker_thread();
+
+    std::mutex _task_mutex;
+    std::condition_variable _task_cv;
+    std::atomic_bool _shutdown_request;
+    std::queue<std::packaged_task<void()>> _task_queue;
+    std::thread _worker_thread;
+};