Inset the shared marker onto the icon glyph

It sat on the icon box's corner, which is 5px outside the artwork on
every side, so the dot read as clipped — half of it hanging over empty
padding with the icon's own drop-shadow falling across it. Nudged in on
both axes: 7px on the desktop, 2px on the dashboard rows.

src/gui/src/css/dashboard.css

@@ -4048,8 +4048,8 @@ body.myapps-reordering .myapps-tile {
 .dashboard-section-files .files-tab .files .row .item-shared-marker {
     width: 7px;
     height: 7px;
-    right: 0;
-    bottom: 0;
+    right: 2px;
+    bottom: 2px;
     box-shadow: 0 0 0 1px white;
 }
 

src/gui/src/css/style.css

@@ -680,8 +680,10 @@ span.header-sort-icon img {
    at the size a row icon allows, and colour is the signal that survives it. */
 .item-shared-marker {
     position: absolute;
-    right: 3px;
-    bottom: 3px;
+    /* Inset onto the glyph. Sitting on the icon box's corner reads as clipped,
+       because the box is 5px wider than the artwork on every side. */
+    right: 7px;
+    bottom: 7px;
     width: 9px;
     height: 9px;
     border-radius: 50%;