internal: introduce new types to avoid unsigned int rollover and signed int overflow (#7216)

* framebuffer: avoid gluint overflow

GLuint was being initialized to -1 and rolling over to unsigned int max,
its defined behaviour but very unnecessery. add a bool and use it for
checking if allocated or not.

* opengl: avoid gluint rollover

-1 rolls over to unsigned int max, use 0xFF instead.

* core: big uint64_t to int type conversion

there were a few uint64_t to int implicit conversions overflowing int
and causing UB, make all monitor/workspaces/windows use the new
typedefs. also fix the various related 64 to 32 implicit conversions
going around found with -Wshorten-64-to-32

src/protocols/ForeignToplevelWlr.cpp

@@ -119,7 +119,7 @@ wl_resource* CForeignToplevelHandleWlr::res() {
 }
 
 void CForeignToplevelHandleWlr::sendMonitor(CMonitor* pMonitor) {
-    if (lastMonitorID == (int64_t)pMonitor->ID)
+    if (lastMonitorID == pMonitor->ID)
         return;
 
     const auto CLIENT = resource->client();

src/protocols/ForeignToplevelWlr.hpp

@@ -20,7 +20,7 @@ class CForeignToplevelHandleWlr {
     SP<CZwlrForeignToplevelHandleV1> resource;
     PHLWINDOWREF                     pWindow;
     bool                             closed        = false;
-    int64_t                          lastMonitorID = -1;
+    MONITORID                        lastMonitorID = MONITOR_INVALID;
 
     void                             sendMonitor(CMonitor* pMonitor);
     void                             sendState();