feat(sidebar): restore section headers and compact separators

HellionChat/Ui/Components/Sidebar.cs

@@ -3,6 +3,7 @@ using Dalamud.Bindings.ImGui;
 using Dalamud.Interface;
 using Dalamud.Interface.Utility.Raii;
 using HellionChat.Code;
+using HellionChat.Resources;
 using HellionChat.Themes;
 using HellionChat.Ui.StyleEngine;
 using HellionChat.Util;
@@ -35,6 +36,10 @@ internal sealed class Sidebar
     // The SelfTest reads it after driving the real Draw — no dead service roundtrip.
     internal int LastRenderedGreetedGlyphCount;
 
+    // B3-4 render observability: section headers actually drawn this frame.
+    // Incremented only in the real header branch; reset at Draw start.
+    internal int LastDrawnSectionHeaderCount;
+
     // Inline mirror of the old TabIconMapping table so the Ui layer carries
     // its own glyph lookup once the standalone file is removed.
     private static readonly Dictionary<string, FontAwesomeIcon> IconByName = new(
@@ -100,6 +105,7 @@ internal sealed class Sidebar
     public void Draw(float windowWidth, IList<Tab> tabs, ref Tab? activeTab)
     {
         LastRenderedGreetedGlyphCount = 0;
+        LastDrawnSectionHeaderCount = 0;
 
         if (!_fonts.FontsReady)
         {
@@ -120,18 +126,74 @@ internal sealed class Sidebar
         var dimAbgr = ColourUtil.RgbaToAbgr(theme.Colors.TextDim);
         var dl = ImGui.GetWindowDrawList();
 
+        // B3-4 sectioned render order (1.5.6 parity): persistent → pinned
+        // TempTabs → unpinned TempTabs. Only the display sequence regroups;
+        // the tab list itself stays untouched and every row keeps its
+        // ORIGINAL list index for PushID, so an open context-menu popup
+        // stays bound to its tab when sectioning moves it visually.
+        var renderOrder = BuildRenderOrder(tabs);
+        var pinnedHeaderRendered = false;
+        var unpinnedHeaderRendered = false;
+        foreach (var i in renderOrder)
+        {
+            var tab = tabs[i];
+            if (TabLifecycleHelpers.IsInPinnedPool(tab) && !pinnedHeaderRendered)
+            {
+                DrawSectionHeader(
+                    HellionStrings.PinTab_SectionHeader,
+                    Plugin.Instance.AutoTellTabsService.PinnedTempTabCount
+                );
+                pinnedHeaderRendered = true;
+            }
+            else if (TabLifecycleHelpers.IsInUnpinnedPool(tab) && !unpinnedHeaderRendered)
+            {
+                DrawSectionHeader(
+                    HellionStrings.AutoTellTabs_SectionHeader,
+                    Plugin.Instance.AutoTellTabsService.ActiveTempTabCount
+                );
+                unpinnedHeaderRendered = true;
+            }
+
+            DrawRow(tab, i, expanded, accentRgba, textAbgr, mutedAbgr, dimAbgr, dl, ref activeTab);
+        }
+    }
+
+    // Section transition marker (1.5.6 parity): the separator always renders,
+    // compact mode suppresses only the header text. Real cursor-advancing
+    // widgets on purpose — rows advance the cursor via InvisibleButton, so a
+    // drawlist-only header would overlap the next row.
+    private void DrawSectionHeader(string header, int count)
+    {
+        ImGui.Separator();
+        if (Plugin.Config.AutoTellTabsCompactDisplay)
+            return;
+
+        ImGui.TextDisabled($"{header} ({count})");
+        LastDrawnSectionHeaderCount++;
+    }
+
+    // Mirror of 1.5.6's BuildSidebarRenderOrder: returns indices into the
+    // live tab list grouped by section, so the list order itself is never
+    // mutated and headers gate on the first tab actually reached per pool
+    // (an empty pool draws neither separator nor header).
+    private static List<int> BuildRenderOrder(IList<Tab> tabs)
+    {
+        var persistent = new List<int>(tabs.Count);
+        var pinned = new List<int>();
+        var unpinned = new List<int>();
         for (var i = 0; i < tabs.Count; i++)
-            DrawRow(
-                tabs[i],
-                i,
-                expanded,
-                accentRgba,
-                textAbgr,
-                mutedAbgr,
-                dimAbgr,
-                dl,
-                ref activeTab
-            );
+        {
+            if (TabLifecycleHelpers.IsInPinnedPool(tabs[i]))
+                pinned.Add(i);
+            else if (TabLifecycleHelpers.IsInUnpinnedPool(tabs[i]))
+                unpinned.Add(i);
+            else
+                persistent.Add(i);
+        }
+
+        persistent.AddRange(pinned);
+        persistent.AddRange(unpinned);
+        return persistent;
     }
 
     private void DrawRow(