fix: marktext#2816 "delete" shortcut on a selected image deletes the …

…text after it (marktext#3088)

fix behavior of "delete" key.
fix behavior of "Ctrl+X" (cut) key behavior.

src/muya/lib/contentState/copyCutCtrl.js

@@ -25,6 +25,7 @@ const copyCutCtrl = ContentState => {
         key,
         token
       })
+      this.selectedImage = null
       return
     }
     const { start, end } = selection.getCursorRange()

src/muya/lib/contentState/deleteCtrl.js

@@ -3,6 +3,13 @@ import selection from '../selection'
 const deleteCtrl = ContentState => {
   // Handle `delete` keydown event on document.
   ContentState.prototype.docDeleteHandler = function (event) {
+    // handle delete selected image
+    const { selectedImage } = this
+    if (selectedImage) {
+      event.preventDefault()
+      this.selectedImage = null
+      return this.deleteImage(selectedImage)
+    }
     if (this.selectedTableCells) {
       event.preventDefault()
       return this.deleteSelectedTableCells()