Fix string slicing bounds error in metric parsing

Fixed critical bug where dashboard crashed with 'begin <= end' slice error
when parsing disk metrics with new naming format. Added bounds checking
to prevent invalid string slicing operations.

- Fixed extract_pool_name string slicing bounds check
- Removed ineffective panic handling that caused infinite loop
- Dashboard now handles new disk collector metrics correctly

dashboard/src/ui/widgets/system.rs

@@ -163,11 +163,7 @@ impl SystemWidget {
         
         for metric in metrics {
             if metric.name.starts_with("disk_") {
-                // Wrap individual metric parsing in error handling
-                if let Ok(pool_name) = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
-                    self.extract_pool_name(&metric.name)
-                })) {
-                    if let Some(pool_name) = pool_name {
+                if let Some(pool_name) = self.extract_pool_name(&metric.name) {
                     let mount_point = self.get_mount_point_for_pool(&pool_name);
                     let pool = pools.entry(pool_name.clone()).or_insert_with(|| StoragePool {
                         name: pool_name.clone(),
@@ -332,10 +328,7 @@ impl SystemWidget {
                             }
                         }
                     }
-                    }  // Close pool_name Some check
-                } else {
-                    tracing::warn!("Failed to extract pool name from metric: {}", metric.name);
-                }  // Close error handling for extract_pool_name
+                }
             }
         }
 
@@ -357,7 +350,9 @@ impl SystemWidget {
                 // Find the second-to-last underscore to get pool name
                 let before_suffix = &metric_name[..suffix_pos];
                 if let Some(drive_start) = before_suffix.rfind('_') {
-                    return Some(metric_name[5..drive_start].to_string()); // Skip "disk_"
+                    if drive_start > 5 {
+                        return Some(metric_name[5..drive_start].to_string()); // Skip "disk_"
+                    }
                 }
             }
             // Handle filesystem metrics: disk_{pool}_fs_{filesystem}_{metric}
@@ -712,13 +707,8 @@ impl Widget for SystemWidget {
             }
         }
 
-        // Update storage from all disk metrics (with error handling)
-        if let Err(e) = std::panic::catch_unwind(std::panic::AssertUnwindSafe(|| {
-            self.update_storage_from_metrics(metrics);
-        })) {
-            tracing::error!("Storage metrics parsing failed, continuing with empty storage: {:?}", e);
-            self.storage_pools = Vec::new();
-        }
+        // Update storage from all disk metrics
+        self.update_storage_from_metrics(metrics);
     }
 
 }