Allow highlighting to be disabled on SelectableText

Changed the interface of SelectableText to allow highlighting to be
disabled in places where it is not applicable (For example, on the
AboutView).

This prevents the need for adding dummy events in places where
highlighting is not applicable, preventing the user from making bad
highlights.

Testing
-------

PASS

Device: iPhone 13 mini
iOS: 17.5
Damus: This version
Steps:
1. Go to a user profile and select some text in their bio. The "highlight" option should not be present.
2. Go to a note and select some text. The "highlight" option should be available

damus/Components/SelectableText.swift

@@ -10,7 +10,7 @@ import SwiftUI
 
 struct SelectableText: View {
     let damus_state: DamusState
-    let event: NostrEvent
+    let event: NostrEvent?
     let attributedString: AttributedString
     let textAlignment: NSTextAlignment
     @State private var showHighlightPost = false
@@ -20,7 +20,7 @@ struct SelectableText: View {
 
     let size: EventViewKind
 
-    init(damus_state: DamusState, event: NostrEvent, attributedString: AttributedString, textAlignment: NSTextAlignment? = nil, size: EventViewKind) {
+    init(damus_state: DamusState, event: NostrEvent?, attributedString: AttributedString, textAlignment: NSTextAlignment? = nil, size: EventViewKind) {
         self.damus_state = damus_state
         self.event = event
         self.attributedString = attributedString
@@ -36,6 +36,7 @@ struct SelectableText: View {
                 font: eventviewsize_to_uifont(size),
                 fixedWidth: selectedTextWidth,
                 textAlignment: self.textAlignment,
+                enableHighlighting: self.enableHighlighting(),
                 showHighlightPost: $showHighlightPost,
                 selectedText: $selectedText,
                 height: $selectedTextHeight
@@ -53,12 +54,18 @@ struct SelectableText: View {
             }
         }
         .sheet(isPresented: $showHighlightPost) {
-            HighlightPostView(damus_state: damus_state, event: event, selectedText: $selectedText)
-                .presentationDragIndicator(.visible)
-                .presentationDetents([.height(selectedTextHeight + 150), .medium, .large])
+            if let event {
+                HighlightPostView(damus_state: damus_state, event: event, selectedText: $selectedText)
+                    .presentationDragIndicator(.visible)
+                    .presentationDetents([.height(selectedTextHeight + 150), .medium, .large])
+            }
         }
         .frame(height: selectedTextHeight)
     }
+    
+    func enableHighlighting() -> Bool {
+        self.event != nil
+    }
 }
 
 fileprivate class TextView: UITextView {
@@ -97,6 +104,7 @@ fileprivate class TextView: UITextView {
     let font: UIFont
     let fixedWidth: CGFloat
     let textAlignment: NSTextAlignment
+    let enableHighlighting: Bool
     @Binding var showHighlightPost: Bool
     @Binding var selectedText: String
     @Binding var height: CGFloat
@@ -115,7 +123,7 @@ fileprivate class TextView: UITextView {
 
         let menuController = UIMenuController.shared
         let highlightItem = UIMenuItem(title: "Highlight", action: #selector(view.highlightText(_:)))
-        menuController.menuItems = [highlightItem]
+        menuController.menuItems = self.enableHighlighting ? [highlightItem] : []
 
         return view
     }

damus/Views/Profile/AboutView.swift

@@ -26,11 +26,7 @@ struct AboutView: View {
         Group {
             if let about_string {
                 let truncated_about = show_full_about ? about_string : about_string.truncateOrNil(maxLength: max_about_length)
-                SelectableText(damus_state: state, event: NostrEvent(
-                    content: "",
-                    keypair: jack_keypair,
-                    createdAt: UInt32(Date().timeIntervalSince1970 - 100)
-                )!, attributedString: truncated_about ?? about_string, textAlignment: self.text_alignment, size: .subheadline)
+                SelectableText(damus_state: state, event: nil, attributedString: truncated_about ?? about_string, textAlignment: self.text_alignment, size: .subheadline)
 
                 if truncated_about != nil {
                     if show_full_about {