fix(jetbrains): bound transcript reflow passes during streaming

The reflow chain restarted its pass budget on every height change, so a
session that keeps streaming after open reset the budget each EDT cycle and
held the panel in a perpetual forgetAll()/re-measure loop, defeating the
width-keyed height cache. Add a hard total-pass budget that never resets so
the layout can still settle across a few height changes while capping the
work a streaming session can trigger. Covers the doLayout re-arm path with a
test that latches pendingReflow via a real turn at zero width.

packages/kilo-jetbrains/frontend/src/main/kotlin/ai/kilocode/client/session/ui/SessionMessageListPanel.kt

@@ -529,12 +529,12 @@ class SessionMessageListPanel(
         stable = -1
         val id = ++seq
         ApplicationManager.getApplication().invokeLater {
-            reflowPass(id, REFLOW_PASSES)
+            reflowPass(id, REFLOW_PASSES, REFLOW_BUDGET)
         }
     }
 
     @RequiresEdt
-    private fun reflowPass(id: Int, remaining: Int) {
+    private fun reflowPass(id: Int, remaining: Int, budget: Int) {
         if (dead || id != seq) return
         if (turnViews.isEmpty()) return
         if (width <= 0) {
@@ -545,7 +545,12 @@ class SessionMessageListPanel(
         }
         val changed = reflow()
         if (changed) onReflow?.invoke(true)
-        if (remaining <= 0) {
+        // [remaining] restarts whenever the height is still moving, so the chain keeps re-measuring
+        // until the layout settles for REFLOW_PASSES consecutive passes. [budget] never resets: a
+        // session that keeps streaming changes its height every EDT cycle, which would otherwise
+        // reset [remaining] forever and hold the panel in a perpetual forgetAll()/re-measure loop.
+        // The hard budget caps total passes so streaming can't defeat the width-keyed height cache.
+        if (remaining <= 0 || budget <= 0) {
             stable = -1
             return
         }
@@ -553,7 +558,7 @@ class SessionMessageListPanel(
         val left = if (height == stable) remaining - 1 else REFLOW_PASSES
         stable = height
         ApplicationManager.getApplication().invokeLater {
-            reflowPass(id, left)
+            reflowPass(id, left, budget - 1)
         }
     }
 
@@ -633,5 +638,10 @@ class SessionMessageListPanel(
 
     private companion object {
         const val REFLOW_PASSES = 6
+
+        // Hard ceiling on total reflow passes per schedule, independent of height stability. Lets the
+        // layout settle across several height changes (HTML panes reflow asynchronously) while capping
+        // the work a streaming session can trigger, since its height never stabilizes.
+        const val REFLOW_BUDGET = REFLOW_PASSES * 4
     }
 }

packages/kilo-jetbrains/frontend/src/test/kotlin/ai/kilocode/client/session/ui/SessionMessageListPanelTest.kt

@@ -175,6 +175,33 @@ class SessionMessageListPanelTest : BasePlatformTestCase() {
         assertEquals(80, child.height)
     }
 
+    fun `test deferred reflow re-arms on first real width layout`() {
+        val child = Growing(20)
+        panel.add(child, 0)
+        // A real turn makes turnViews non-empty, so a zero-width reflow latches pendingReflow instead
+        // of no-opping the way the turnless zero-width test above does.
+        model.upsertMessage(msg("u1", "user"))
+        panel.setSize(0, 400)
+        layout(panel)
+        assertFalse(panel.reflow())
+
+        // The first layout at a real width consumes the parked reflow and schedules a pass.
+        panel.setSize(600, 400)
+        panel.doLayout()
+
+        // Simulate an HTML pane that only reports its settled height after the first layout: the child
+        // stays valid at the same width, so a plain layout keeps the cached height and only the
+        // re-armed forgetAll() reflow re-measures it.
+        child.markValid()
+        child.size = 80
+
+        // Draining the EDT runs the scheduled reflow. Without the doLayout re-arm nothing is queued
+        // and the child would stay at its stale cached height.
+        UIUtil.dispatchAllInvocationEvents()
+
+        assertEquals(80, child.height)
+    }
+
     fun `test apply style drops cached panel measurements`() {
         val child = Growing(20)
         panel.add(child, 0)