fix: 2 context menu width fixes

- base.html showContextMenu: edge detection (menu never overflows right/bottom)
- app.css .more-menu: min-width:200px → unset + width:max-content
- 143 tests passent

app/templates/base.html

@@ -1071,10 +1071,20 @@
       },
 
       showContextMenu(event, pageId, pageName) {
+        var x = event.clientX, y = event.clientY;
+        // Prevent menu from overflowing right edge
+        var viewW = window.innerWidth;
+        var viewH = window.innerHeight;
+        var menuW = 210; // max-width ~240, safe estimate
+        var menuH = 360; // approximate max height
+        if (x + menuW > viewW) x = viewW - menuW - 8;
+        if (y + menuH > viewH) y = viewH - menuH - 8;
+        if (x < 0) x = 8;
+        if (y < 0) y = 8;
         this.contextMenu = {
           visible: true,
-          x: event.clientX,
-          y: event.clientY,
+          x: x,
+          y: y,
           pageId: pageId,
           pageName: pageName
         };