docs: update changelog and version for v1.13.0a6 (#5214)

docs/en/changelog.mdx

@@ -4,6 +4,26 @@ description: "Product updates, improvements, and bug fixes for CrewAI"
 icon: "clock"
 mode: "wide"
 ---
+<Update label="Apr 01, 2026">
+  ## v1.13.0a6
+
+  [View release on GitHub](https://github.com/crewAIInc/crewAI/releases/tag/1.13.0a6)
+
+  ## What's Changed
+
+  ### Documentation
+  - Fix RBAC permission levels to match actual UI options (#5210)
+  - Update changelog and version for v1.13.0a5 (#5200)
+
+  ### Performance
+  - Reduce framework overhead by implementing a lazy event bus and skipping tracing when disabled (#5187)
+
+  ## Contributors
+
+  @alex-clawd, @joaomdmoura, @lucasgomide
+
+</Update>
+
 <Update label="Mar 31, 2026">
   ## v1.13.0a5