feat: improve textbox editor behaviour

text_editor.go

@@ -306,6 +306,8 @@ func (e *textEditor) handleVisualKey(key tea.KeyMsg, multiline bool, wrapWidth i
 		e.yankSelection(wrapWidth)
 	case keyMatches(k, e.keys.Vim.Delete):
 		e.deleteSelection(wrapWidth)
+	case keyMatches(k, e.keys.Vim.ReplaceCharacter):
+		e.substituteSelection(wrapWidth)
 	case keyMatches(k, e.keys.Vim.Paste):
 		e.pasteClipboard(true, wrapWidth)
 	default:
@@ -407,6 +409,20 @@ func (e *textEditor) deleteSelection(wrapWidth int) {
 	e.stopVisual()
 }
 
+func (e *textEditor) substituteSelection(wrapWidth int) {
+	start, end, ok := e.selectionBounds(wrapWidth)
+	if !ok {
+		e.stopVisual()
+		return
+	}
+	runes := []rune(e.Text)
+	e.Text = string(append(runes[:start], runes[end:]...))
+	e.Cursor = start
+	e.Mode = textEditorInsert
+	e.visualLine = false
+	e.clearPending()
+}
+
 func (e *textEditor) pasteClipboard(replaceSelection bool, wrapWidth int) {
 	if e.clipboard == nil {
 		e.clipboard = systemTextClipboard{}