fix(editor): update expand/collapse logic and threshold

- Set editor to collapsed state after resizing.
- Adjust expand/collapse label visibility and text based on collapsed state.
- Increase `minDevinLineThreshold` from 1 to 5 for better usability.

Author: phodal

core/src/main/kotlin/cc/unitmesh/devti/sketch/ui/code/CodeHighlightSketch.kt

@@ -47,7 +47,7 @@ open class CodeHighlightSketch(
     val editorLineThreshold: Int = 6
 ) : JBPanel<CodeHighlightSketch>(BorderLayout()), DataProvider, LangSketch, Disposable {
     private val devinLineThreshold = 10
-    private val minDevinLineThreshold = 1
+    private val minDevinLineThreshold = 5
     private var isDevIns = false
 
     private var textLanguage: String? = null

core/src/main/kotlin/cc/unitmesh/devti/sketch/ui/code/EditorFragment.kt

@@ -106,10 +106,12 @@ class EditorFragment(var editor: EditorEx, private val editorLineThreshold: Int
     fun resizeForNewThreshold(newThreshold: Int) {
         content.preferredSize = calculatePreferredSize(content.preferredSize, newThreshold)
 
+        setCollapsed(true)
+
         val linesCount = editor.document.lineCount
-        expandCollapseTextLabel.isVisible = linesCount > newThreshold
-        expandCollapseTextLabel.text = "More lines"
-        expandCollapseTextLabel.icon = AllIcons.General.ChevronDown
+        expandCollapseTextLabel.isVisible = linesCount > editorLineThreshold
+        expandCollapseTextLabel.text = if (collapsed) "More lines" else ""
+        expandCollapseTextLabel.icon = if (collapsed) AllIcons.General.ChevronDown else AllIcons.General.ChevronUp
 
         content.revalidate()
         content.repaint()