Refactor MatchResult: Performance optimization and DRY implementation

[ArtemZhyto]

Description

This PR focuses on optimizing the core matching results logic to improve performance and maintainability. It addresses technical debt in the MatchResult component, making it more robust for future feature expansions.

Key Changes:

• Performance Optimization: Wrapped studyById dictionary creation in useMemo. Previously, this dictionary was re-computed on every render ($O(N)$ complexity), which is inefficient for large study sets.
• DRY Refactoring: Unified the list rendering logic into a single internal helper. This eliminated significant code duplication across the Matched, Undetermined, and Unmatched sections.
• Defensive Engineering: Added safety checks for study lookups to prevent runtime crashes if the data state is inconsistent.

Why this is important:

As we move towards more dynamic rendering models (like search-first UX), the core result-grouping logic needs to be as efficient and clean as possible to handle rapid state updates without UI lag.

Testing

• Verified that all three study categories (Matched, Undetermined, Unmatched) still render correctly.
• Confirmed that "TrialMatchInfo" displays correctly for each study.