Add an assertion to the discrete_space function and a death test

[tpadioleau]

No description provided.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 89.80%. Comparing base (a40f2d3) to head (6584eaf).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
include/ddc/discrete_space.hpp	50.00%	1 Missing and 1 partial ⚠️

❌ Your patch status has failed because the patch coverage (50.00%) is below the target coverage (100.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #875      +/-   ##
==========================================
- Coverage   89.92%   89.80%   -0.13%     
==========================================
  Files          55       55              
  Lines        2859     2863       +4     
  Branches      974      976       +2     
==========================================
  Hits         2571     2571              
- Misses         92       95       +3     
- Partials      196      197       +1     

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

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.