merge: codeql findings #1 and #2

.github/workflows/build.yml

@@ -11,6 +11,13 @@ on:
     branches: [main]
   workflow_dispatch:
 
+# Minimum permissions for a build-only workflow: read the repo, nothing
+# else. Closes the CodeQL "Workflow does not contain permissions" alert
+# and matches the principle-of-least-privilege the security guide
+# recommends for workflows that don't push or create releases.
+permissions:
+  contents: read
+
 jobs:
   build:
     name: Build (Release)

ChatTwo/Util/ImGuiUtil.cs

@@ -94,18 +94,24 @@ internal static class ImGuiUtil
         foreach (var part in csText.Split(["\r\n", "\r", "\n"], StringSplitOptions.None))
         {
             var bytes = Encoding.UTF8.GetBytes(part);
-            fixed (byte* rawText = bytes)
-            {
-                var text = rawText;
-                var textEnd = text + bytes.Length;
 
-                // empty string
-                if (text == null)
+            // Empty splits (consecutive newlines) leave bytes.Length at 0
+            // and the textEnd pointer below would coincide with text. The
+            // ImGuiNative word-wrap calls treat that as undefined input,
+            // and the CodeQL "unvalidated local pointer arithmetic" alert
+            // also flags it. Render an empty line and skip the unsafe
+            // block entirely for this iteration.
+            if (bytes.Length == 0)
             {
                 ImGui.TextUnformatted("");
                 continue;
             }
 
+            fixed (byte* rawText = bytes)
+            {
+                var text = rawText;
+                var textEnd = text + bytes.Length;
+
                 var widthLeft = ImGui.GetContentRegionAvail().X;
                 var endPrevLine = ImGuiNative.CalcWordWrapPositionA(ImGui.GetFont().Handle, ImGuiHelpers.GlobalScale, text, textEnd, widthLeft);
                 if (endPrevLine == null)