chore: production standardisation of the server codebase

Final submission readiness: cleanups, checklist, strict grader fix

chore: final calibration and validator fixes for OpenEnv submission

refactor: calibrate scores for progression Easy > Medium > Hard

feat: finalize OpenEnv alignment and calibrate rewards for QA

Add Java rate limiter and C++ event dispatcher tasks; update requirements

feat: add interactive web dashboard for space

refactor: update relative imports to resolve pathing issues after project restructuring

chore: initialize python virtual environment and dependencies