major navbar overhaul: .btn-primary.btn-xl now reads CONT GAME and links to the user's most recently active game; log out functionality transferred to new BYE .btn-abandon abutting login spans; tooltips for each asserted via new FTs.test_navbar methods to appear w.in visible area

src/templates/core/base.html

@@ -86,11 +86,13 @@
                 portal.style.left = Math.round(cleft) + 'px';
                 var cardCenterY = rect.top + rect.height / 2;
                 if (cardCenterY < window.innerHeight / 2) {
-                    portal.style.top = Math.round(rect.top) + 'px';
-                    portal.style.transform = 'translate(-50%, calc(-100% - 0.5rem))';
-                } else {
+                    // button in upper half → show below
                     portal.style.top = Math.round(rect.bottom) + 'px';
                     portal.style.transform = 'translate(-50%, 0.5rem)';
+                } else {
+                    // button in lower half → show above
+                    portal.style.top = Math.round(rect.top) + 'px';
+                    portal.style.transform = 'translate(-50%, calc(-100% - 0.5rem))';
                 }
             }
 
@@ -140,6 +142,7 @@
                     var form = btn.closest('form');
                     show(btn, btn.dataset.confirm, function () {
                         if (form) form.submit();
+                        else if (btn.dataset.href) window.location.href = btn.dataset.href;
                     });
                 }, true);
             });