docs: update TOC

README.md

@@ -27,6 +27,32 @@ Some use cases are to store objects with the best values according to the follow
 
 <!-- START doctoc generated TOC please keep comment here to allow auto update -->
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+<details>
+<summary>Table of Contents</summary>
+
+- [Design goals](#design-goals)
+- [Examples](#examples)
+  - [Constructing fronts](#constructing-fronts)
+  - [Insertion](#insertion)
+  - [Reference points](#reference-points)
+  - [Iterators](#iterators)
+  - [Queries](#queries)
+  - [Dominance](#dominance)
+  - [Indicators](#indicators)
+  - [Archives](#archives)
+- [Functions](#functions)
+- [Benchmarks](#benchmarks)
+- [Integration](#integration)
+  - [Packages](#packages)
+  - [Build from source](#build-from-source)
+  - [CMake targets](#cmake-targets)
+  - [Other build systems](#other-build-systems)
+- [Limitations](#limitations)
+- [Contributing](#contributing)
+- [Thanks](#thanks)
+- [References](#references)
+
+</details>
 <!-- END doctoc generated TOC please keep comment here to allow auto update -->
 
 ## Design goals