[lint] Add clang-format rule for header sorting

.clang-format

@@ -53,14 +53,72 @@ ForEachMacros:   [ foreach, Q_FOREACH ]
 # Sort headers by main include file (implicit priority 0),
 # then project and private includes, then system headers
 IncludeCategories:
-  - Regex:     '^<([a-z|_]+)>' # standard library headers
-    Priority:  1
-  - Regex:     '^(<[A-z]+)'    # dependency headers
-    Priority:  2
-  - Regex:     '^(<|")dart/'   # DART headers
-    Priority:  3
-  - Regex:     '^".*'          # headers relative to this project
-    Priority:  4
+  - Regex: '^".*\.h(pp)?"$' # headers relative to this project
+    Priority: 1
+
+  # DART headers
+  - Regex: '^<dart\/config.hpp>$'
+    Priority: 10
+  - Regex: '^<dart\/test\/.*\.h(pp)?>$'
+    Priority: 20
+  - Regex: '^<dart\/python\/.*\.h(pp)?>$'
+    Priority: 21
+  - Regex: '^<dart\/gui\/.*\.h(pp)?>$'
+    Priority: 22
+  - Regex: '^<dart\/utils\/.*\.h(pp)?>$'
+    Priority: 23
+  - Regex: '^<dart\/simulation\/.*\.h(pp)?>$'
+    Priority: 24
+  - Regex: '^<dart\/constraint\/.*\.h(pp)?>$'
+    Priority: 25
+  - Regex: '^<dart\/collision\/.*\.h(pp)?>$'
+    Priority: 26
+  - Regex: '^<dart\/dynamics\/.*\.h(pp)?>$'
+    Priority: 27
+  - Regex: '^<dart\/optimizer\/.*\.h(pp)?>$'
+    Priority: 28
+  - Regex: '^<dart\/lcpsolver\/.*\.h(pp)?>$'
+    Priority: 29
+  - Regex: '^<dart\/integration\/.*\.h(pp)?>$'
+    Priority: 30
+  - Regex: '^<dart\/math\/.*\.h(pp)?>$'
+    Priority: 31
+  - Regex: '^<dart\/common\/.*\.h(pp)?>$'
+    Priority: 32
+  - Regex: '^<dart\/.*\.h(pp)?>$'
+    Priority: 33
+  - Regex: '^<dart\/external\/.*\.h(pp)?>$'
+    Priority: 34
+
+  # 3rd-party headers
+  - Regex: '^<.*\.h(pp)?>$'
+    Priority: 50
+  - Regex: '^<.*\/.*>$'
+    Priority: 50
+
+  # C++ standard library headers, then C
+  # TODO(JS): Add when new C++ STL header begins with "c" is found
+  - Regex: "^<charconv>$"
+    Priority: 100
+  - Regex: "^<chrono>$"
+    Priority: 100
+  - Regex: "^<compare>$"
+    Priority: 100
+  - Regex: "^<complex>$"
+    Priority: 100
+  - Regex: "^<concepts>$"
+    Priority: 100
+  - Regex: "^<condition_variable>$"
+    Priority: 100
+  - Regex: "^<coroutine>$"
+    Priority: 100
+  - Regex: "^<c.*>$" # C standard library headers
+    Priority: 110
+  - Regex: "^<([a-z|_]+)>$"
+    Priority: 100
+
+  - Regex: ".*"
+    Priority: 999
 IndentCaseLabels: true
 IndentPPDirectives: BeforeHash
 IndentFunctionDeclarationAfterType: false