chore: adding notes on implementation

[dansiegel]

GitHub Issue (If applicable): #

• closes unoplatform/uno.extensions-private#101
• closes unoplatform/uno.extensions-private#104

PR Type

What kind of change does this PR introduce?

• Bugfix

What is the current behavior?

Maui Embedding remains decoupled from Maui

What is the new behavior?

Maui Embedding makes use of the Maui host applications and initializes a "Current" instance of them so that references to the concrete types will not cause fatal exceptions that prevent some controls from rendering.

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• Docs have been added/updated which fit documentation template. (for bug fixes / features)
• Unit Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• Wasm UI Tests are not showing unexpected any differences. Validate PR Screenshots Compare Test Run results.
• Contains NO breaking changes
• Updated the Release Notes
• Associated with an issue (GitHub or internal)

Other information

Internal Issue (If applicable):