fixed ignoring clicks on UI elements and partial fix for keys

src/mirrage/gui/src/gui.cpp

-#include <sf2/sf2.hpp>
 #include <mirrage/gui/gui.hpp>
+#include <sf2/sf2.hpp>
 
 #include <mirrage/asset/asset_manager.hpp>
 #include <mirrage/input/events.hpp>
@@ -373,6 +373,7 @@ namespace mirrage::gui {
 						handle_key(evt.type == SDL_KEYDOWN, evt.key.keysym.scancode);
 						return evt.key.keysym.sym == SDLK_ESCAPE || !io.WantCaptureKeyboard;
 
+					case SDL_MOUSEBUTTONUP: return !io.WantCaptureMouse;
 					case SDL_MOUSEBUTTONDOWN:
 						if(evt.button.button > 0 && evt.button.button < 4) {
 							_mouse_pressed[evt.button.button - 1] = true;

src/mirrage/input/include/mirrage/input/input_manager.hpp

@@ -102,7 +102,7 @@ namespace mirrage::input {
 		void _on_mouse_motion(const SDL_MouseMotionEvent& motion);
 
 		void _poll_events();
-		void _handle_event(SDL_Event& event);
+		void _handle_event(SDL_Event& event, bool filtered);
 
 	  private:
 		class Gamepad;

src/mirrage/input/src/input_manager.cpp

@@ -201,9 +201,7 @@ namespace mirrage::input {
 			                             [&](auto f) { return !f->propagate(event); })
 			                != _event_filter.end();
 
-			if(!filtered) {
-				_handle_event(event);
-			}
+			_handle_event(event, filtered);
 		}
 
 		for(auto& f : _event_filter) {
@@ -212,8 +210,11 @@ namespace mirrage::input {
 	}
 
 
-	void Input_manager::_handle_event(SDL_Event& event)
+	void Input_manager::_handle_event(SDL_Event& event, bool filtered)
 	{
+		if(filtered)
+			return; // TODO: don't filter key/button-up events if the down event has already been send
+
 		switch(event.type) {
 			case SDL_TEXTINPUT: _mailbox.send<Char_input>(event.text.text); break;
 
@@ -339,7 +340,8 @@ namespace mirrage::input {
 		if(SDL_IsGameController(joystick_id)) {
 			SDL_GameController* controller = SDL_GameControllerOpen(joystick_id);
 			if(controller) {
-				_gamepads.emplace_back(std::make_unique<Gamepad>(gsl::narrow<Input_source>(_gamepads.size() + 1), controller, *_mapper));
+				_gamepads.emplace_back(std::make_unique<Gamepad>(
+				        gsl::narrow<Input_source>(_gamepads.size() + 1), controller, *_mapper));
 				_mailbox.send<Source_added>(Input_source(_gamepads.size()));
 			} else {
 				std::cerr << "Could not open gamecontroller " << joystick_id << ": " << SDL_GetError()