Add unit tests

[pfefferle]

Summary

Add unit tests for the namespaced classes.

Test Coverage

• Indieweb\Indieweb - Main plugin class tests

  • Version constant and plugin constants
  • Singleton pattern
  • Hook registration
  • Action firing

• Indieweb\Hcard\User - H-Card user class tests

  • Silos configuration
  • Address and extra fields
  • URL cleaning and validation
  • H-Card display defaults
  • H-Card rendering

• Indieweb\Relme\Domain_Icon_Map - Domain icon mapping tests

  • Domain splitting
  • URL to icon name mapping
  • Known domains (GitHub, Twitter, Bluesky, etc.)
  • Special schemes (mailto, sms)
  • Filter application

Structure

Tests follow the same directory structure as the includes:

tests/phpunit/
├── bootstrap.php
└── tests/includes/
    ├── class-test-indieweb.php
    ├── hcard/
    │   └── class-test-user.php
    └── relme/
        └── class-test-domain-icon-map.php