Add BreakBeforeConceptDeclarations key to ClangFormat configuration

The previous ClangFormat configuration was developed for use with ClangFormat 11.0.1. The version of ClangFormat now in
use by Arduino tools is 14.0.0.

This configuration key was added in the interim.

The key value set here was chosen in order to:

- Align with behavior of the Arduino IDE 1.x "Auto Format" feature.

The `false` value is the most permissive, allowing the user to break or not break at their whim.

Since the concepts feature was added to C++ relatively recently, there is not any established style in official Arduino
code.

Author: per1234

other/clang-format-configuration/.clang-format

@@ -51,6 +51,7 @@ BraceWrapping:
 BreakAfterJavaFieldAnnotations: false
 BreakBeforeBinaryOperators: NonAssignment
 BreakBeforeBraces: Attach
+BreakBeforeConceptDeclarations: false
 BreakBeforeInheritanceComma: false
 BreakBeforeTernaryOperators: true
 BreakConstructorInitializers: BeforeColon

other/clang-format-configuration/notes.md

@@ -20,6 +20,12 @@ This key is irrelevant because we define all configuration keys.
 
 This key is ignored when `BreakBeforeBraces` is set to anything other than `Custom`.
 
+## `BreakBeforeConceptDeclarations`
+
+`true` forces the break.
+
+`false` allows the user to break or not break at their whim, in alignment with the Arduino IDE 1.x formatter behavior and Arduino's `AlwaysBreakTemplateDeclarations: No` configuration.
+
 ## `BreakBeforeInheritanceComma`
 
 Seems to be a backwards compatibility name for `BreakInheritanceList: BeforeComma`: