feat: support late observables

[amondnet]

Describe the changes proposed in this Pull Request.

Fixes #919

---

Pull Request Checklist

• [x] If the changes are being made to code, ensure the version in pubspec.yaml is updated.
• [x] Increment the major/minor/patch/patch-count, depending on the complexity of change
• [x] Add the necessary unit tests to ensure the coverage does not drop
• [x] Update the Changelog to include all changes made in this PR, organized by version
• [x] Run the melos run set_version command from the root directory
• [x] Include the necessary reviewers for the PR
• [x] Update the docs if there are any API changes or additions to functionality

[netlify[bot]]

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[codecov[bot]]

Codecov Report

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

Comparison is base (60f07a0) 99.00% compared to head (1b5d3fc) 99.00%.

Additional details and impacted files

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[amondnet]

@pavanpodila I rebased to the main branch and resolved the conflict.