Chore: Plugin refactoring according to PSR4

[up1512001]

Overview

This PR refactors the OneUpdate plugin to follow PSR-4 autoloading standards and modern PHP best practices, improving code organization, maintainability, and developer experience.

Code Organization & Architecture

PSR-4 Autoloading: Restructured all PHP classes to follow PSR-4 naming conventions and directory structure
Namespace Organization: Organized code into logical modules under OneUpdate\Modules*

• Core: Core functionality (Assets, DB, REST)
• Plugin: Plugin-specific features (Admin, Cache, S3, Settings, VIP)
• Rest: REST API controllers
• Settings: Settings management

Checklist

• I have read the Contribution Guidelines.
• I have read the Development Guidelines.
• My code is tested to the best of my abilities.
• My code passes all lints (ESLint etc.).
• My code has detailed inline documentation.
• I have updated the project documentation as needed.
• I have added a changeset for this PR using npm run changeset.

[Copilot]

Pull request overview

This PR refactors the OneUpdate plugin to follow PSR-4 autoloading standards and modern PHP best practices. The refactoring reorganizes code into logical modules, improves code organization, implements proper encryption for sensitive data, and enhances the development tooling infrastructure.

Key changes:

• Migrated from classmap autoloading to PSR-4 namespace structure under OneUpdate\Modules\*
• Implemented encryption for sensitive credentials (API keys, GitHub tokens, S3 credentials)
• Enhanced build tooling with TypeScript support and improved webpack configuration
• Added comprehensive code quality tools (PHPStan, expanded PHPCS rules)
• Restructured REST API controllers with a base abstract class

Reviewed changes

Copilot reviewed 88 out of 95 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
webpack.config.js	Updated build paths and added TypeScript support with path aliases
uninstall.php	Enhanced multisite support and comprehensive cleanup
tsconfig.json	Added TypeScript configuration with strict type checking
phpunit.xml.dist	New PHPUnit configuration for testing
phpstan.neon.dist	Added static analysis configuration
phpcs.xml.dist	Comprehensive PHPCS rules with Slevomat standards
package.json	Updated dependencies and build scripts
oneupdate.php	Simplified entry point using autoloader
inc/Main.php	New main plugin class with registrable pattern
inc/Autoloader.php	PSR-4 autoloader with graceful failure handling
inc/Encryptor.php	AES-256-GCM encryption for sensitive data
inc/Modules/*	Reorganized code into logical modules
inc/Contracts/*	Interfaces and traits for architecture
composer.json	Updated to PSR-4 autoloading with modern dev dependencies

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[justlevine]

Looks great!
As with previous migrations, I'm not sure what exactly is preexisting and what is from the refactor (for some reason git isn't recognizing them as renames), so use your discretion

[justlevine]

This is intentionally PHP 8.1 and not 8.0? If so we should update the docs + plugin headers + phpcs/phpstan configs. If not, we should drop this + the require below.

[up1512001]

Yes as aws/aws-sdk-php requires minimum 8.1 PHP.
https://aws.amazon.com/blogs/developer/announcing-the-end-of-support-for-php-runtimes-8-0-x-and-below-in-the-aws-sdk-for-php/

[justlevine]

Okay, make sure to bump readme.txt and remove it from the (commented out) phpunit matrix in test.yml

[justlevine]

Once those last 2 comments are handled, go ahead and merge - no reason to wait on me.

[up1512001]

Merging since it's already being approved.