fix(ui): set preferred size for buttons in SingleFileDiffView

- Set preferred size for all buttons to 32x32 pixels for consistent UI.
- Simplify response handling in DiffStreamHandler by removing unnecessary CodeFence parsing.

Author: phodal

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

@@ -154,7 +154,8 @@ class DiffStreamHandler(
                 }
             }
 
-            handleFinishedResponse(suggestion.toString())
+            val code = CodeFence.parse(suggestion.toString())
+            handleFinishedResponse(code.text)
         }
     }
 

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

@@ -154,7 +154,6 @@ class SingleFileDiffView(
         val rollback = JButton("Rollback").apply {
             icon = AllIcons.Actions.Rollback
             border = BorderFactory.createEmptyBorder()
-            preferredSize = Dimension(32, 32)
             toolTipText = AutoDevBundle.message("sketch.patch.action.rollback.tooltip")
             isEnabled = undoManager.isUndoAvailable(fileEditor)
 
@@ -170,7 +169,6 @@ class SingleFileDiffView(
         val viewDiffButton = JButton("View").apply {
             icon = AllIcons.Actions.ListChanges
             border = BorderFactory.createEmptyBorder()
-            preferredSize = Dimension(32, 32)
             toolTipText = AutoDevBundle.message("sketch.patch.action.viewDiff.tooltip")
 
             addMouseListener(object : MouseAdapter() {
@@ -182,7 +180,6 @@ class SingleFileDiffView(
 
         val runStreamButton = JButton("Apply").apply {
             icon = AllIcons.Actions.RunAll
-            preferredSize = Dimension(32, 32)
             border = BorderFactory.createEmptyBorder()
             toolTipText = AutoDevBundle.message("sketch.patch.action.runDiff.tooltip")
             isEnabled = appliedPatch?.status == ApplyPatchStatus.SUCCESS
@@ -208,7 +205,6 @@ class SingleFileDiffView(
 
         val repairButton = JButton("Repair").apply {
             icon = AllIcons.Toolwindows.ToolWindowBuild
-            preferredSize = Dimension(32, 32)
             border = BorderFactory.createEmptyBorder()
             toolTipText = AutoDevBundle.message("sketch.patch.action.repairDiff.tooltip")
             isEnabled = appliedPatch?.status != ApplyPatchStatus.SUCCESS