[KBM] Fix remaps to arrow keys/Home/Ins, etc not working with Windows Terminal (#7143)

* Added MapVirtualKey call to set scancode before calling SendInput

* Updated comment

* Update comment with link

* Added test for dummy key scan code

src/modules/keyboardmanager/common/Helpers.cpp

@@ -192,6 +192,10 @@ namespace KeyboardManagerHelper
             keyEventArray[index].ki.dwFlags |= KEYEVENTF_EXTENDEDKEY;
         }
         keyEventArray[index].ki.dwExtraInfo = extraInfo;
+
+        // Set wScan to the value from MapVirtualKey as some applications may use the scan code for handling input, for instance, Windows Terminal ignores non-character input which has scancode set to 0. 
+        // MapVirtualKey returns 0 if the key code does not correspond to a physical key (such as unassigned/reserved keys). More details at https://github.com/microsoft/PowerToys/pull/7143#issue-498877747
+        keyEventArray[index].ki.wScan = (WORD)MapVirtualKey(keyCode, MAPVK_VK_TO_VSC);
     }
 
     // Function to set the dummy key events used for remapping shortcuts, required to ensure releasing a modifier doesn't trigger another action (For example, Win->Start Menu or Alt->Menu bar)

src/modules/keyboardmanager/test/SetKeyEventTests.cpp

@@ -41,5 +41,19 @@ namespace RemappingLogicTests
                 Assert::AreEqual(true, bool(input[i].ki.dwFlags & KEYEVENTF_EXTENDEDKEY));
             }
         }
+        
+        // Test if SetKeyEvent sets the scan code field to 0 for dummy key
+        TEST_METHOD (SetKeyEvent_ShouldSetScanCodeFieldTo0_WhenArgumentIsDummyKey)
+        {
+            const int nInputs = KeyboardManagerConstants::DUMMY_KEY_EVENT_SIZE;
+            INPUT input[nInputs] = {};
+
+            int index = 0;
+            KeyboardManagerHelper::SetDummyKeyEvent(input, index, 0);
+
+            // Assert that wScan for both inputs is 0
+            Assert::AreEqual<unsigned int>(0, input[0].ki.wScan);
+            Assert::AreEqual<unsigned int>(0, input[1].ki.wScan);
+        }
     };
 }