[idd] ipc: connect LGInput to LGIdd

Move the reusable named-pipe endpoint and shared support code into
the LGCommon static library.

Run a dedicated server in LGIdd and a reconnecting client in
LGInput, with device-lifecycle handling and report framing.

Refactor the helper pipe to use the same endpoint implementation.

idd/LGInput/CHIDDevice.h

@@ -30,4 +30,5 @@ public:
   static NTSTATUS SubmitReport(
     _In_reads_bytes_(size) const void * report,
     _In_ size_t size);
+  static NTSTATUS ClearReports();
 };