fix: Replaced assert with ValueError in stochastic_occupancy

[igopalakrishna]

Fixes #28

This pull request resolves the issue by replacing assert statements with explicit ValueError exceptions in the example file mentioned, smart_control/simulator/stochastic_occupancy.py.

Using ValueError is better practice as assert statements can be disabled in production environments, which would otherwise silently ignore important precondition checks.

• Tests pass
• No documentation changes were necessary for this change.

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[s2t2]

Nice, thanks @igopalakrishna for taking up this issue. 🙌 I provided some specific comments below for the first instance you fixed.

In general, it would be nice to have a single PR that addresses all the instances across the codebase.

With the error raising implemented, we should now be able to add some tests to ensure each of the errors is triggered when we pass in certain invalid conditions. If you are able to add a corresponding test for each error, that would be awesome!

[s2t2]

I think we want the second string on its own line, to avoid line-too-long errors.

[s2t2]

let's consider using more natural language in the error message, like "earliest expected arrival must come before latest expected arrival, earliest expected departure must come before latest expected departure", etc.

[s2t2]

@igopalakrishna should we close this PR in favor of #113 ?