Updated the profile icon to default to using two characters (initials if possible)

SignalUtilitiesKit/Profile Pictures/Identicon+ObjC.swift

@@ -8,7 +8,17 @@ public final class Identicon : NSObject {
         if content.count > 2 && content.hasPrefix("05") {
             content.removeFirst(2)
         }
-        let layer = icon.generateLayer(with: size, text: content.substring(to: 1))
+        let initials: String = content
+            .split(separator: " ")
+            .compactMap { word in word.first.map { String($0) } }
+            .joined()
+        let layer = icon.generateLayer(
+            with: size,
+            text: (initials.count >= 2 ?
+                initials.substring(to: 2).uppercased() :
+                content.substring(to: 2).capitalized
+            )
+        )
         let rect = CGRect(origin: CGPoint.zero, size: layer.frame.size)
         let renderer = UIGraphicsImageRenderer(size: rect.size)
         return renderer.image { layer.render(in: $0.cgContext) }

SignalUtilitiesKit/Profile Pictures/PlaceholderIcon.swift

@@ -37,7 +37,6 @@ public class PlaceholderIcon {
     }
     
     private func getTextLayer(with diameter: CGFloat, colour: CGColor? = nil, text: String) -> CALayer {
-        let text = text.capitalized
         let font = UIFont.boldSystemFont(ofSize: diameter / 2)
         let height = NSString(string: text).boundingRect(with: CGSize(width: diameter, height: CGFloat.greatestFiniteMagnitude),
             options: .usesLineFragmentOrigin, attributes: [ NSAttributedString.Key.font : font ], context: nil).height