Fix Notices Class Static Method Error and Improve Documentation

Overview

This PR resolves a critical PHP error in the Notices class and adds comprehensive documentation for the Admin Notices functionality.

Changes Made

🐛 Bug Fix: Notices Class Static Method Error

• File: src/Admin/Notices.php
• Issue: The add() method was declared as static but attempted to use $this->notices, causing a "Cannot use '$this' in non-object context" error
• Solution: Removed the static keyword from the add() method to allow proper instance method behavior

Before:

public static function add( array $args ) {
    // ... code using $this->notices
}

After:

public function add( array $args ) {
    // ... code using $this->notices
}

📚 Documentation Enhancement: Admin Notices Usage

• File: readme.md
• Added: Complete "Admin Notices" section with usage examples
• Includes:
  • Proper instantiation examples
  • Available notice types (success, error, warning, info)
  • Configuration options and parameters
  • Code examples showing best practices

Impact

Breaking Change Notice

⚠️ Breaking Change: The Notices::add() method is no longer static. Code calling this method must be updated:

Old Usage (No longer works):

Notices::add( $args );

New Usage (Required):

$notices = new Notices();
$notices->add( $args );

Benefits

• ✅ Resolves fatal PHP errors when using the Notices class
• ✅ Provides clear documentation for developers
• ✅ Maintains WordPress admin notice standards
• ✅ Enables proper instance-based notice management

Files Changed

• src/Admin/Notices.php (1 line changed)
• readme.md (21 lines added)

Testing

• Verified Notices class instantiation works correctly
• Confirmed add() method functions without errors
• Validated notice rendering in WordPress admin

Closes #23