feat: add modal Vim editing to notes

Sources/Conjure/NotesTextView.swift

@@ -3,7 +3,7 @@ import AppKit
 private let literalTaskMarker = NSAttributedString.Key("Conjure.literalTaskMarker")
 private let sourceTaskAttachment = NSAttributedString.Key("Conjure.sourceTaskAttachment")
 private let sourceListParagraph = NSAttributedString.Key("Conjure.sourceListParagraph")
-private let listWhitespace = NSAttributedString.Key("Conjure.listWhitespace")
+let listWhitespace = NSAttributedString.Key("Conjure.listWhitespace")
 
 private final class ListAttachment: NSTextAttachment {
     let source: NSAttributedString
@@ -61,12 +61,18 @@ final class NotesTextView: NSTextView, @MainActor NSLayoutManagerDelegate {
     private var tasks: [(range: NSRange, attachment: ListAttachment)] = []
     private var checkboxes: [NSButton] = []
     private var horizontalSelection: (anchor: Int, head: Int)?
+    var vimState = NotesVimState()
+    var vimModeChanged: (() -> Void)?
+    var vimEnabled = false {
+        didSet { resetVim() }
+    }
 
     var markdownContents: NSAttributedString { Self.serialize(attributedString()) }
     var markdownString: String { markdownContents.string }
 
     func setMarkdownContents(_ contents: NSAttributedString) {
         horizontalSelection = nil
+        resetVim()
         textStorage?.setAttributedString(Self.render(contents))
         refreshTasks()
     }
@@ -232,6 +238,7 @@ final class NotesTextView: NSTextView, @MainActor NSLayoutManagerDelegate {
     }
 
     override func keyDown(with event: NSEvent) {
+        if handleVimKey(event) { return }
         if event.keyCode == 48,
            event.modifierFlags.intersection([.command, .control, .option, .shift]) == .shift,
            delegate?.textView?(self, doCommandBy: #selector(NSResponder.insertBacktab(_:))) == true {
@@ -240,6 +247,18 @@ final class NotesTextView: NSTextView, @MainActor NSLayoutManagerDelegate {
         super.keyDown(with: event)
     }
 
+    override func resignFirstResponder() -> Bool {
+        let resigned = super.resignFirstResponder()
+        if resigned { clearVimCommand() }
+        return resigned
+    }
+
+    override func mouseDown(with event: NSEvent) {
+        if vimEnabled && vimMode != .insert { resetVim() }
+        else { clearVimCommand() }
+        super.mouseDown(with: event)
+    }
+
     override func insertText(_ insertString: Any, replacementRange: NSRange) {
         let replacement: NSAttributedString
         if let attributed = insertString as? NSAttributedString {