Remove Baseline section, fix filters and radar layout

- Removed Baseline section from Bluetooth sidebar (no longer needed)
- Fixed device filter buttons not working (changed display to '' instead
  of 'block' to preserve flexbox layout)
- Fixed proximity radar being cut off by bottom panels:
  - Added overflow: hidden to radar panel
  - Constrained bottom panels to max-height: 120px
  - Made radar content respect parent boundaries

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

static/css/index.css

@@ -3280,17 +3280,28 @@ header h1 .tagline {
 .bt-radar-panel {
     flex: 1;
     min-height: 0;
+    overflow: hidden;
+    display: flex;
+    flex-direction: column;
+}
+
+.bt-radar-panel #btProximityRadar {
+    flex: 1;
+    min-height: 0;
+    overflow: hidden;
 }
 
 .bt-bottom-panels {
     display: flex;
     gap: 12px;
     flex-shrink: 0;
+    max-height: 120px;
 }
 
 .bt-compact-panel {
     flex: 1;
     min-width: 0;
+    overflow: hidden;
 }
 
 /* Bluetooth Device Detail Panel */