Fix disk usage calculation and regex pattern

SharedLibrary/Extension/String.swift

@@ -29,16 +29,7 @@ public extension String {
     }
 
     var splittedByWhitespace: [String] {
-        guard let trimWhiteSpaceRegEx = try? NSRegularExpression(pattern: "/ +/g") else {
-            return []
-        }
-        let trimmed = trimWhiteSpaceRegEx.stringByReplacingMatches(
-            in: self,
-            options: [],
-            range: NSRange(location: 0, length: count),
-            withTemplate: " "
-        )
-        return trimmed.split(separator: " ").map { String($0) }
+        split(separator: " ").filter { !$0.isEmpty }.map { String($0) }
     }
 
     var numericOnly: String {

eul/Store/DiskStore.swift

@@ -29,12 +29,29 @@ class DiskStore: ObservableObject, Refreshable {
         return list?.disks.filter { $0.name == config.diskSelection }.first
     }
 
+    private var rootAttributes: (size: UInt64, free: UInt64)? {
+        guard
+            let attrs = try? FileManager.default.attributesOfFileSystem(forPath: "/"),
+            let size = attrs[.systemSize] as? UInt64,
+            let free = attrs[.systemFreeSize] as? UInt64
+        else {
+            return nil
+        }
+        return (size, free)
+    }
+
     var ceilingBytes: UInt64? {
-        selectedDisk?.size ?? list?.disks.reduce(0) { $0 + $1.size }
+        if let selected = selectedDisk {
+            return selected.size
+        }
+        return rootAttributes?.size
     }
 
     var freeBytes: UInt64? {
-        selectedDisk?.freeSize ?? list?.disks.reduce(0) { $0 + $1.freeSize }
+        if let selected = selectedDisk {
+            return selected.freeSize
+        }
+        return rootAttributes?.free
     }
 
     var usageString: String {