Feature: Migrate loading indicators to NETworkManager

[BornToBeRoot]

Please provide some details about this pull request:

• Migrated the loading indicator from https://github.com/zeluisping/LoadingIndicators.WPF to this repo, because the repo looks unmaintained and has problems with the latest MahApps version.

Copilot:

Details

This pull request includes significant changes to the `NETworkManager` project, focusing on the removal of an external dependency and the introduction of a custom loading indicator control. The most important changes include the removal of `LoadingIndicators.WPF` references, the addition of new loading indicator styles, and the implementation of a custom `LoadingIndicator` control.

Removal of external dependency:

• Source/NETworkManager/App.xaml: Removed references to LoadingIndicators.WPF resource dictionaries.
• Source/NETworkManager/NETworkManager.csproj: Removed LoadingIndicators.WPF package reference.

Addition of custom loading indicator:

• Source/NETworkManager/LoadingIndicators.cs: Implemented a custom LoadingIndicator control with dependency properties for SpeedRatio and IsActive.
• Source/NETworkManager/Resources/Styles/LoadingIndicatorArcsStyle.xaml: Added a new style for the custom loading indicator with arc animations.
• Source/NETworkManager/Resources/Styles/LoadingIndicatorPulseStyle.xaml: Added a new style for the custom loading indicator with pulse animations.

Namespace updates:

• Source/NETworkManager/Views/DiscoveryProtocolView.xaml: Updated XAML to use the custom LoadingIndicator control. [1] [2]
• Source/NETworkManager/Views/IPApiDNSResolverWidgetView.xaml: Updated XAML to use the custom LoadingIndicator control. [1] [2]
• Source/NETworkManager/Views/IPApiIPGeolocationWidgetView.xaml: Updated XAML to use the custom LoadingIndicator control.

ToDo:

• Update changelog to reflect this changes

---

By submitting this pull request, I confirm the following:

• I have read and understood the contributing guidelines and the code of conduct.
• I have have added my name, username or email to the contributors list or don't want to.
• The code or resource is compatible with the GNU General Public License v3.0.