Fix filesystem usage_percent parsing and remove hardcoded status

1. Add missing _fs_ filter to usage_percent parsing in dashboard
2. Fix agent to use calculated fs_status instead of hardcoded Status::Ok

This completes the disk collector auto-discovery by ensuring filesystem
usage percentages and status indicators display correctly.

dashboard/src/ui/widgets/system.rs

@@ -180,7 +180,8 @@ impl SystemWidget {
                     });
 
                     // Parse different metric types
-                    if metric.name.contains("_usage_percent") {
+                    if metric.name.contains("_usage_percent") && !metric.name.contains("_fs_") {
+                        // Only use drive-level metrics for pool totals, not filesystem metrics
                         if let MetricValue::Float(usage) = metric.value {
                             pool.usage_percent = Some(usage);
                             pool.status = metric.status.clone();