Update services widget memory display and formatting

Improve services widget to show consistent usage/total format for both
RAM and Disk columns, using system totals when no service quotas exist.

Changes:
- Change column header from "Memory (GB)" to "RAM (GB)"
- Remove "GB" units from memory values (units now in header)
- Add system memory total detection from /proc/meminfo
- Use system memory total as default quota for services without limits
- Services now show "5.2/32.0" format for both RAM and disk

Both RAM and Disk columns now consistently display usage/quota format
where quota is either service-specific limit or system total capacity.

dashboard/src/ui/services.rs

@@ -50,7 +50,7 @@ fn render_metrics(
     let mut data = WidgetData::new(
         title, 
         Some(WidgetStatus::new(widget_status)),
-        vec!["Service".to_string(), "Memory (GB)".to_string(), "CPU".to_string(), "Disk".to_string()]
+        vec!["Service".to_string(), "RAM (GB)".to_string(), "CPU".to_string(), "Disk".to_string()]
     );
 
 
@@ -142,11 +142,11 @@ fn format_memory_value(used: f32, quota: f32) -> String {
     let quota_gb = quota / 1000.0;
     
     if quota > 0.05 {
-        format!("{:.1}/{:.1} GB", used_gb, quota_gb)
+        format!("{:.1}/{:.1}", used_gb, quota_gb)
     } else if used > 0.05 {
-        format!("{:.1} GB", used_gb)
+        format!("{:.1}", used_gb)
     } else {
-        "0.0 GB".to_string()
+        "0.0".to_string()
     }
 }