internal: new shared_ptr and weak_ptr implementation (#5883)

moves std::shared_ptrs to a new implementation

Advantages:
- you can dereference a weak_ptr directly. This will obviously segfault on a nullptr deref if it's expired.
   - this is useful to avoid the .lock() hell where we are 100% sure the pointer _should_ be valid. (and if it isn't, it should throw.)
- weak_ptrs are still valid while the SP is being destroyed.
   - reasoning: while an object (e.g. CWindow) is being destroyed, its `weak_ptr self` should be accessible (the sp is still alive, and so is CWindow), but it's not because by stl it's already expired (to prevent resurrection)
   - this impl solves it differently. w_p is expired, but can still be dereferenced and used. Creating `s_p`s is not possible anymore, though.
   - this is useful in destructors and callbacks.

src/protocols/TearingControl.cpp

@@ -22,7 +22,7 @@ void CTearingControlProtocol::onManagerResourceDestroy(wl_resource* res) {
 }
 
 void CTearingControlProtocol::onGetController(wl_client* client, CWpTearingControlManagerV1* pMgr, uint32_t id, wlr_surface* surf) {
-    const auto CONTROLLER = m_vTearingControllers.emplace_back(std::make_unique<CTearingControl>(std::make_shared<CWpTearingControlV1>(client, pMgr->version(), id), surf)).get();
+    const auto CONTROLLER = m_vTearingControllers.emplace_back(std::make_unique<CTearingControl>(makeShared<CWpTearingControlV1>(client, pMgr->version(), id), surf)).get();
 
     if (!CONTROLLER->good()) {
         pMgr->noMemory();
@@ -67,7 +67,7 @@ void CTearingControl::updateWindow() {
     if (pWindow.expired())
         return;
 
-    pWindow.lock()->m_bTearingHint = hint == WP_TEARING_CONTROL_V1_PRESENTATION_HINT_ASYNC;
+    pWindow->m_bTearingHint = hint == WP_TEARING_CONTROL_V1_PRESENTATION_HINT_ASYNC;
 }
 
 bool CTearingControl::good() {