feat: close dialogs on backdrop click

Native dialog elements don't close on backdrop click by default.
Added click handlers that check if click target is the dialog itself
(not its children) to enable this expected UX behavior.

src/app.js

@@ -579,8 +579,14 @@ function init() {
 	// Dialogs
 	elements.helpBtn.addEventListener("click", showHelp);
 	elements.helpDialogClose.addEventListener("click", closeHelpDialog);
+	elements.helpDialog.addEventListener("click", (e) => {
+		if (e.target === elements.helpDialog) closeHelpDialog();
+	});
 	elements.resetBtn.addEventListener("click", showResetConfirmation);
 	elements.resetDialogClose.addEventListener("click", closeResetDialog);
+	elements.resetDialog.addEventListener("click", (e) => {
+		if (e.target === elements.resetDialog) closeResetDialog();
+	});
 	elements.cancelReset.addEventListener("click", closeResetDialog);
 	elements.confirmReset.addEventListener("click", handleResetConfirm);