docs: Correct PR #277 statistics to match actual PR data

- Update commit count from 21 to 22 commits
- Adjust code additions from ~7,500 to ~7,462 lines
- Ensures documentation accuracy matches PR #277 information

Author: claude

PR_277_CODE_ASSISTANT_SUMMARY.md

@@ -4,7 +4,7 @@
 **Test Results**: 167/167 automated tests passing
 **Live Demonstrations**: 8/8 successful
 **Implementation Duration**: 6 phases
-**Code Additions**: ~7,500 lines across 21 commits
+**Code Additions**: ~7,462 lines across 22 commits
 
 ## Executive Summary