Fix ambiguous Color init(hex:) extension

Removed duplicate Color.init(hex:) extension from AllTasksView.swift as it's now defined in DesignSystem.swift.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

iosApp/iosApp/Task/AllTasksView.swift

@@ -259,31 +259,3 @@ extension Array where Element == ResidenceWithTasks {
         }
     }
 }
-
-extension Color {
-    /// Initialize Color from hex string (e.g., "#007AFF" or "007AFF")
-    init?(hex: String) {
-        let hex = hex.trimmingCharacters(in: CharacterSet.alphanumerics.inverted)
-        var int: UInt64 = 0
-        Scanner(string: hex).scanHexInt64(&int)
-        let a, r, g, b: UInt64
-        switch hex.count {
-        case 3: // RGB (12-bit)
-            (a, r, g, b) = (255, (int >> 8) * 17, (int >> 4 & 0xF) * 17, (int & 0xF) * 17)
-        case 6: // RGB (24-bit)
-            (a, r, g, b) = (255, int >> 16, int >> 8 & 0xFF, int & 0xFF)
-        case 8: // ARGB (32-bit)
-            (a, r, g, b) = (int >> 24, int >> 16 & 0xFF, int >> 8 & 0xFF, int & 0xFF)
-        default:
-            return nil
-        }
-        
-        self.init(
-            .sRGB,
-            red: Double(r) / 255,
-            green: Double(g) / 255,
-            blue:  Double(b) / 255,
-            opacity: Double(a) / 255
-        )
-    }
-}