Improve project structure docs

Co-authored-by: Felix Arntz <[email protected]>

Author: westonruter

AGENTS.md

@@ -6,7 +6,14 @@ This is a monorepo for the WordPress Performance Team, containing a collection o
 
 * **Purpose:** To develop and maintain a suite of plugins that improve the performance of WordPress sites. All should be considered potential for future candidates for merging into WordPress core.
 * **Technologies:** PHP, JavaScript, CSS, a variety of testing and linting tools.
-* **Architecture:** This is a monorepo containing multiple WordPress plugins. The main plugin is `performance-lab`, which acts as a hub for performance features, most of which are standalone plugins located in the `plugins` directory (although some come from other repos). Each plugin has its own tests located in its respective `tests` subdirectory.
+
+### Project Structure
+
+* `/bin`: Custom CLI commands and scripts for certain development workflows.
+* `/plugins`: The actual WordPress plugins that are developed in this monorepo.
+* `/plugins/*`: An individual WordPress plugin folder.
+* `/plugins/*/tests`: PHPUnit tests for the specific WordPress plugin.
+* `/tools`: Setup and configuration files for various tools, such as linting and testing.
 
 ## Building and Running