Refactor time-based bar aggregation

[stastnypremysl]

Draft Pull Request

Summary

• interval_type type from str to enum
• Refactored TimeBarAggregator.init, so the variable initialization are before methods calling
• Added validation of time_bars_origin
• Fixed the first bar issue on left_open interval (https://nt-dist.stty.cz/issues/20250509-1-first-bar-not-generated-on-millisecond-bug/)
• Fixed the bug with self.next_close_ns doesn't change, when no tick is sent
• Fixed potential bug with first bar skipped on batch processing
• Added _invalidate_skip_first_non_full_bar_on_exact_start for batch proccesing
• Added step validation to BarSpecification
• TBD

Related Issues/PRs

https://nt-dist.stty.cz/issues/20250509-1-first-bar-not-generated-on-millisecond-bug/

Type of change

• [x] Bug fix (non-breaking)
• [x] New feature (non-breaking)
• [x] Breaking change (impacts existing behavior)
• [ ] Documentation update
• [x] Maintenance / chore

Breaking change details (if applicable)

Release notes

• [ ] I added a concise entry to RELEASES.md that follows the existing conventions (when applicable)

Testing

Ensure new or changed logic is covered by tests.

• [ ] Affected code paths are already covered by the test suite
• [ ] I added/updated tests to cover new or changed logic

[CLAassistant]

All committers have signed the CLA.

[stastnypremysl]

Closing this, as the change have been/will be distributed across different PRs.