docs: Improve pubspec metadata

[ABausG]

Description

Improve Pubspec Metadata by adding Funding Link, Topics and Screenshots

Checklist

• [x] I have updated/added tests for ALL new/updated/fixed functionality.
• [x] I have updated/added relevant documentation and added code (documentation) comments where necessary.
• [x] I have updated/added relevant examples in example or documentation.

Breaking Change?

• [ ] Yes, this PR is a breaking change.
• [x] No, this PR is not a breaking change.

Related Issues

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.00%. Comparing base (9e86097) to head (08cdbbd).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #283 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 3 3 Lines 104 104 ========================================= Hits 104 104 ```

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