Add maxMarks to LLM marking formula evaluation context

[mlt47]

Fixed a bug in LLM marking formula evaluation where the question's maxMarks was not being included in its context for evaluation.

---

Pull Request Check List

• Unit Tests & Regression Tests Added (I will add a separate PR for this so that this change is tested with this week's manual regression tests)
• Removed Unnecessary Logs/System.Outs/Comments/TODOs
• Updated Release Procedure & Documentation (& Considered Implications to Previous Versions)
• Peer-Reviewed

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 3 lines in your changes missing coverage. Please review.

Project coverage is 34.16%. Comparing base (fbc0db4) to head (e210227).
Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
...m/cl/dtg/isaac/quiz/IsaacLLMFreeTextValidator.java	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #650      +/-   ##
==========================================
- Coverage   34.16%   34.16%   -0.01%     
==========================================
  Files         520      520              
  Lines       23243    23245       +2     
  Branches     2849     2849              
==========================================
  Hits         7941     7941              
- Misses      14501    14503       +2     
  Partials      801      801              

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.