fix: hide desktop table-toolbar on mobile + fix sparkline overflow (#16)

- Add .table-toolbar to mobile hide list (was rendering duplicate
  'TRACKED PLAYERS' header above the mobile section-head)
- Change .m-card__body grid to minmax(0, 1fr) auto so the stats
  column can shrink below content size
- Add min-width: 0 to .m-card__stats for proper grid shrinking
- Remove grid-row: span 2 from .m-card__sparkline (single-row grid)
- Remove overflow: visible from .m-chart-spark so the end-dot stays
  within the SVG viewport

public/css/mobile.css

@@ -24,6 +24,7 @@
     .kpi-strip        { display: none !important; }
     .add-bar          { display: none !important; }
     .footnote         { display: none !important; }
+    .table-toolbar    { display: none !important; }
 
     /* Hide desktop search card on mobile (mobile has .m-search-input instead) */
     .card-section     { display: none; }
@@ -345,7 +346,7 @@
 
     .m-card__body {
         display: grid;
-        grid-template-columns: 1fr auto;
+        grid-template-columns: minmax(0, 1fr) auto;
         gap: 10px;
         align-items: center;
         margin-top: 8px;
@@ -355,6 +356,7 @@
         display: flex;
         flex-direction: column;
         gap: 6px;
+        min-width: 0;
     }
 
     .m-stat-row {
@@ -396,13 +398,12 @@
     .m-card__sparkline {
         display: flex;
         align-items: center;
-        justify-content: center;
-        grid-row: span 2;
+        justify-content: flex-end;
+        flex-shrink: 0;
     }
 
     .m-chart-spark {
         display: block;
-        overflow: visible;
     }
 
     /* ── Player card expand panel ───────────────────── */