Fix handler processing time display for sub-millisecond values

- Add formatProcessingTime function to display microseconds for values < 1ms
- Show 0 µs for times < 0.001ms, X.X µs for times < 0.01ms
- Show X.XXX ms for times < 1ms, X.XX ms for times >= 1ms
- Apply formatting to both average and min/max time displays

internal/templates/status.html

@@ -202,6 +202,18 @@
             return num.toLocaleString();
         }
         
+        function formatProcessingTime(ms) {
+            if (ms < 0.001) {
+                return (ms * 1000).toFixed(0) + ' µs';
+            } else if (ms < 0.01) {
+                return (ms * 1000).toFixed(1) + ' µs';
+            } else if (ms < 1) {
+                return ms.toFixed(3) + ' ms';
+            } else {
+                return ms.toFixed(2) + ' ms';
+            }
+        }
+        
         function updatePrefixDistribution(elementId, distribution) {
             const container = document.getElementById(elementId);
             container.innerHTML = '';
@@ -252,11 +264,11 @@
                     </div>
                     <div class="metric">
                         <span class="metric-label">Avg Time</span>
-                        <span class="metric-value">${handler.avg_process_time_ms.toFixed(2)} ms</span>
+                        <span class="metric-value">${formatProcessingTime(handler.avg_process_time_ms)}</span>
                     </div>
                     <div class="metric">
                         <span class="metric-label">Min/Max Time</span>
-                        <span class="metric-value">${handler.min_process_time_ms.toFixed(2)} / ${handler.max_process_time_ms.toFixed(2)} ms</span>
+                        <span class="metric-value">${formatProcessingTime(handler.min_process_time_ms)} / ${formatProcessingTime(handler.max_process_time_ms)}</span>
                     </div>
                 `;