Release 2.0.25

Add comprehensive tests for UserAgentHelpers.GetDevice

Refactor `UserAgentHelpersTests` to include detailed test cases
for `GetDevice` method. Removed unused `using` directives and
added `EasyExtensions.Helpers` namespace.

Added pseudocode plan as a comment to outline test scenarios.
Implemented test methods to validate behavior for various user
agent strings, including null/whitespace, bots, scripts, TVs,
consoles, iOS, Android, ChromeOS, desktop OS, and fallback cases.
Used `[TestCase]` attributes for parameterized testing and
assertions to ensure expected outputs.