Implement Tickgen for MonoVertex

[vigith]

Summary

Pave a path for including builtins into MonoVertex

Use Cases

support Builtins

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Message from the maintainers:

If you wish to see this enhancement implemented please add a 👍 reaction to this issue! We often sort issues this way to know what to prioritize.

### Tasks
- [ ] https://github.com/numaproj/numaflow/pull/2114
- [ ] implement tickgen using source trait
- [ ] use numaflow-models for tickgen