Fix WiFi table columns and channel chart overflow

Table fixes:
- Add BSSID column header to match data columns
- Remove vendor column from table rows (6 columns total)
- Update placeholder colspan to 6

Layout fixes:
- Use minmax() for right columns to allow shrinking
- Add overflow handling to layout container
- Add min-width: 0 to analysis panel for proper grid behavior
- Add overflow-x: auto to channel chart container

Channel chart fixes:
- Reduce bar width from 20px to 14px
- Reduce bar spacing from 4px to 2px
- Reduce padding for more compact display
- Use viewBox for responsive SVG scaling

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

static/js/modes/wifi.js

@@ -731,7 +731,6 @@ const WiFiMode = (function() {
                     <span class="security-badge ${securityClass}">${escapeHtml(network.security)}</span>
                 </td>
                 <td class="col-clients">${network.client_count || 0}</td>
-                <td class="col-vendor">${escapeHtml(network.vendor || '-')}</td>
             </tr>
         `;
     }