Fix: raise ValueError when run_simplex exceeds max iterations

[MeriemBchini]

Summary

run_simplex() currently returns an empty dictionary when the maximum
iteration limit is reached, providing no indication of failure.

Changes

• Replaced silent return {} with a descriptive ValueError
• Added iteration tracking for better debugging

Why this matters

This prevents silent failures and allows users to distinguish between:

• valid empty solutions
• non-convergence (cycling, unbounded problems)

Example

Before:
run_simplex() → {}

After:
ValueError: Simplex did not converge within 100 iterations

Testing

• Existing functionality unaffected
• Added manual test for max iteration failure

[algorithms-keeper]

Closing this pull request as invalid

@MeriemBchini, this pull request is being closed as none of the checkboxes have been marked. It is important that you go through the checklist and mark the ones relevant to this pull request. Please read the Contributing guidelines.

If you're facing any problem on how to mark a checkbox, please read the following instructions:

• Read a point one at a time and think if it is relevant to the pull request or not.
• If it is, then mark it by putting a x between the square bracket like so: [x]

NOTE: Only [x] is supported so if you have put any other letter or symbol between the brackets, that will be marked as invalid. If that is the case then please open a new pull request with the appropriate changes.