feat(toast): use toasts from context

[danielkaxis]

Describe your changes

Enables use of multiple ToastAnchors throughout the application sharing the toasts.
Moves the ToastMap to the ToastProvider

Issue ticket number and link

• Fixes Toast: Show toast in fullscreen #241

Checklist before requesting a review

• I have performed a self-review of my own code
• I have verified that the code builds perfectly fine on my local system
• I have added tests that prove my fix is effective or that my feature works
• I have commented my code, particularly in hard-to-understand areas
• I have verified that my code follows the style already available in the repository
• I have made corresponding changes to the documentation