sys/windows: add WM_SYSCOMMAND related constants

core/sys/windows/types.odin

@@ -594,6 +594,31 @@ SM_CARETBLINKINGENABLED :: 0x2002
 SM_CONVERTIBLESLATEMODE :: 0x2003
 SM_SYSTEMDOCKED         :: 0x2004
 
+// System Menu Command Values
+SC_SIZE         :: 0xF000
+SC_MOVE         :: 0xF010
+SC_MINIMIZE     :: 0xF020
+SC_MAXIMIZE     :: 0xF030
+SC_NEXTWINDOW   :: 0xF040
+SC_PREVWINDOW   :: 0xF050
+SC_CLOSE        :: 0xF060
+SC_VSCROLL      :: 0xF070
+SC_HSCROLL      :: 0xF080
+SC_MOUSEMENU    :: 0xF090
+SC_KEYMENU      :: 0xF100
+SC_ARRANGE      :: 0xF110
+SC_RESTORE      :: 0xF120
+SC_TASKLIST     :: 0xF130
+SC_SCREENSAVE   :: 0xF140
+SC_HOTKEY       :: 0xF150
+SC_DEFAULT      :: 0xF160
+SC_MONITORPOWER :: 0xF170
+SC_CONTEXTHELP  :: 0xF180
+SC_SEPARATOR    :: 0xF00F
+SCF_ISSECURE    :: 0x00000001
+SC_ICON         :: SC_MINIMIZE
+SC_ZOOM         :: SC_MAXIMIZE
+
 CW_USEDEFAULT : c_int : -2147483648
 
 SIZE_RESTORED  :: 0

core/sys/windows/user32.odin

@@ -192,3 +192,7 @@ CreateWindowW :: #force_inline proc "stdcall" (
 		lpParam,
 	)
 }
+
+GET_SC_WPARAM :: #force_inline proc(wparam: WPARAM) -> i32 {
+	return i32(wparam) & 0xFFF0
+}