fix(diff): handle edge case in line highlighting

Add boundary check to prevent index out of bounds when highlighting lines in the diff editor.

Author: phodal

core/src/main/kotlin/cc/unitmesh/devti/diff/DiffStreamHandler.kt

@@ -195,6 +195,10 @@ class DiffStreamHandler(
 
     private fun initUnfinishedRangeHighlights() {
         for (i in startLine..endLine) {
+            if (i >= editor.document.lineCount) {
+                break
+            }
+
             val highlighter = editor.markupModel.addLineHighlighter(
                 unfinishedKey, min(
                     i, editor.document.lineCount - 1

core/src/main/kotlin/cc/unitmesh/devti/sketch/ui/patch/DiffLangSketch.kt

@@ -172,7 +172,7 @@ class DiffLangSketch(private val myProject: Project, private var patchContent: S
 
 fun showSingleDiff(project: Project, patchContent: String, handleAccept: (() -> Unit)?) {
     val editorProvider = FileEditorProvider.EP_FILE_EDITOR_PROVIDER.extensionList.firstOrNull {
-        it.javaClass.simpleName == "DiffPatchFileEditorProvider"
+        it.javaClass.simpleName == "DiffPatchFileEditorProvider" || it.javaClass.simpleName == "DiffEditorProvider"
     }
 
     if (editorProvider != null) {