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/desktop/Window.cpp

@@ -1243,7 +1243,7 @@ bool CWindow::isEffectiveInternalFSMode(const eFullscreenMode MODE) {
     return (eFullscreenMode)std::bit_floor((uint8_t)m_sFullscreenState.internal) == MODE;
 }
 
-int CWindow::workspaceID() {
+WORKSPACEID CWindow::workspaceID() {
     return m_pWorkspace ? m_pWorkspace->m_iID : m_iLastWorkspace;
 }