perf(ui): cache auto-tell tab tint and icon per tab

HellionChat/Configuration.cs

@@ -482,6 +482,16 @@ public class Tab
     // session. NonSerialized because the temp tab itself is session-only.
     [NonSerialized] public bool IsGreeted;
 
+    // v1.4.2 — TabTintCache uses separate validation keys per cache so a
+    // TellTarget change picked up by GetTint can't strand GetIcon (or vice
+    // versa) with a stale entry that looks fresh on the shared key.
+    [NonSerialized] internal string? _cachedTintTellName;
+    [NonSerialized] internal uint _cachedTintTellWorld;
+    [NonSerialized] internal uint _cachedTellTint;
+    [NonSerialized] internal string? _cachedIconTellName;
+    [NonSerialized] internal uint _cachedIconTellWorld;
+    [NonSerialized] internal string? _cachedTellIcon;
+
     public bool Matches(Message message)
     {
         if (!message.Matches(SelectedChannels, ExtraChatAll, ExtraChatChannels))

HellionChat/Ui/ChatLogWindow.cs

@@ -1571,7 +1571,7 @@ public sealed class ChatLogWindow : Window
                     {
                         // v1.2.0 — Hash-Color-Tint differenziert parallele Auto-Tell-Tabs
                         // visuell ohne dass User pro Tab manuell ein Custom-Icon setzen muss.
-                        iconColor = AutoTellTabTint.For(tab.TellTarget.Name, tab.TellTarget.World);
+                        iconColor = TabTintCache.GetTint(tab);
                     }
                     else
                     {

HellionChat/Ui/TabIconMapping.cs

@@ -61,7 +61,7 @@ internal static class TabIconMapping
         string? autoTellGlyph = null;
         if (tab.IsTempTab && tab.TellTarget != null && tab.TellTarget.IsSet())
         {
-            autoTellGlyph = AutoTellTabTint.IconFor(tab.TellTarget.Name, tab.TellTarget.World);
+            autoTellGlyph = TabTintCache.GetIcon(tab);
         }
 
         var glyph = TabIconGlyphResolver.ResolveGlyphName(tab, autoTellGlyph);

HellionChat/Ui/TabTintCache.cs

@@ -0,0 +1,36 @@
+namespace HellionChat.Ui;
+
+// Per-Tab cache wrapper around the pure AutoTellTabTint hash helpers.
+// Each cache (tint, icon) carries its own name+world validation key so
+// neither read path mutates the other's state — refilling one never
+// invalidates the other. No string allocation in the steady-state lookup.
+internal static class TabTintCache
+{
+    public static uint GetTint(Tab tab)
+    {
+        var name = tab.TellTarget.Name;
+        var world = tab.TellTarget.World;
+        if (tab._cachedTintTellName != name || tab._cachedTintTellWorld != world)
+        {
+            tab._cachedTintTellName = name;
+            tab._cachedTintTellWorld = world;
+            tab._cachedTellTint = AutoTellTabTint.For(name, world);
+        }
+        return tab._cachedTellTint;
+    }
+
+    public static string GetIcon(Tab tab)
+    {
+        var name = tab.TellTarget.Name;
+        var world = tab.TellTarget.World;
+        if (tab._cachedTellIcon is null
+            || tab._cachedIconTellName != name
+            || tab._cachedIconTellWorld != world)
+        {
+            tab._cachedIconTellName = name;
+            tab._cachedIconTellWorld = world;
+            tab._cachedTellIcon = AutoTellTabTint.IconFor(name, world);
+        }
+        return tab._cachedTellIcon;
+    }
+}