after commit 4b4971c it uses m_iFbAllocated and deletes if upon calling
release() but Renderbuffer generates directly on m_iFb without calling
alloc() meaning it wont be deleted on release(), set m_iFbAllocated to
true after generating the buffer.
* watchdog: dont detach and cause race condition
instead of detaching and causing a race condition on destruction where
the thread is alive and watchdog has been destroyed, check if its
joinable and join it on destruction.
causes heap use after free on exit of compositor.
* render: add checks for compositor shutting down
avoid member call on null pointer, if the g_pHyprRenderer is destroyed
we can call the member makeEGLCurrent on it, causes undefined behaviour
on destruction of the compositor/hyprrenderer.
found with ubsan.
