feat: type de jauge configurable (compact / standard)

- ServerConfig: champ gauge_type (défaut "compact")
- CSS: classes .gs-* pour la BatteryGauge standard (label + bar 9px + gloss interne)
- Grid: helper renderGaugeRow() — sélectionne compact ou standard selon la config
- Grid: rerenderAll() pour appliquer le changement sans recharger la page
- Popup config serveur: select "Type de jauge" dans la section Affichage des tuiles

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

dashboard/js/popups.js

@@ -312,6 +312,11 @@ const Popups = (() => {
               <input type="range" class="scfg-slider" min="10" max="18" value="${cfg.font_size ?? 13}"
                 oninput="this.nextElementSibling.textContent=this.value+'px'" id="s-font">
               <span class="scfg-val">${cfg.font_size ?? 13}px</span></div>
+            <div class="scfg-row"><label>Type de jauge</label>
+              <select class="scfg-select" id="s-gauge-type">
+                <option value="compact" ${(cfg.gauge_type ?? 'compact') === 'compact' ? 'selected' : ''}>Compact</option>
+                <option value="standard" ${(cfg.gauge_type ?? 'compact') === 'standard' ? 'selected' : ''}>Standard</option>
+              </select></div>
           </div>
           <div style="display:flex;flex-direction:column;gap:8px">
             <div class="scfg-sec-title">SEUILS D'ALERTE</div>
@@ -372,11 +377,14 @@ const Popups = (() => {
             warn_disk: parseInt(document.getElementById('s-warn-disk')?.value ?? 75),
             retention_days: parseInt(document.getElementById('s-retention')?.value ?? 30),
             chart_duration_min: parseInt(document.getElementById('s-chart-dur')?.value ?? 30),
+            gauge_type: document.getElementById('s-gauge-type')?.value ?? 'compact',
         };
+        const prevGaugeType = App.serverConfig?.gauge_type ?? 'compact';
         await API.putServerConfig(cfg);
         App.serverConfig = cfg;
         document.documentElement.style.setProperty('--tile-min', cfg.tile_min_width + 'px');
         document.body.style.fontSize = cfg.font_size + 'px';
+        if (cfg.gauge_type !== prevGaugeType) Grid.rerenderAll();
         hideSrvCfg();
     }