style: dashboard LED smaller, TipModal flags fullbleed + subtle picker buttons

- Dashboard: LED digits 20px (was 26px) — less crowded between flags
- MatchCard: topRow margins for better badge alignment
- TipModal: flags now object-fit:cover (fullbleed)
- TipModal: picker buttons less glossy — reduced shine from 55% to 12%,
  smaller shadow, subtler hover effect

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/src/pages/DashboardPage.module.css

@@ -123,7 +123,7 @@
 
 .ledDigit, .ledColon {
   font-family: 'DSEG7', 'Courier New', monospace;
-  font-size: 26px;
+  font-size: 20px;
   color: #FECC4C;
   display: inline-block;
   text-align: center;
@@ -135,11 +135,11 @@
 }
 
 .ledDigit {
-  width: 18px;
+  width: 14px;
 }
 
 .ledColon {
-  width: 8px;
+  width: 6px;
 }
 
 .heroGroup {