[ID-52]Fix "start_date" and "end_date" timestamp, "archived", "public" and set "complete" in the result

Description

Fix "start_date" and "end_date" timestamp, "archived", "public" and set "complete" in the result

**Resolves #52

[ ] Bug fix (non-breaking change which fixes an issue).
[x] New feature (non-breaking change which adds functionality).
[ ] Breaking change (fix or feature that would cause existing functionality to not work as expected).
[ ] Other (any another change that does not fall in one of the above categories.)

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[x] I have updated the CHANGELOG.
[x] I have read the Contributor Guidelines.
[x] I have performed a self-review of my own code.
[x] I have commented my code, particularly in hard-to-understand areas.
[ ] My change requires updating the documentation.
[x] I have made necessary changes to the documentation.
[ ] I have added tests related to my changes.
[x] My changes generate no new warnings.
[ ] New and existing unit tests pass locally with my changes.
[ ] Any dependent changes have been merged and published in downstream modules.