fix: fail on multiple matches by default and add replaceAll option for bulk replacement

[hashemix]

📌 Summary

updates the edit_file tool to fail on multiple matches by default , and adds a replaceAll parameter to the edit_file tool that allows replacing all occurrences of oldText when multiple matches are found in a file.

🔍 Related Issues

• edit_file silently replaces first match when oldText appears multiple times #76

✨ Changes Made

• Added error handling when multiple matches found by default
• Added replaceAll optional parameter to apply_file_edits function
• Updated EditFile tool schema to include replaceAll option
• Added 5 new test cases for multiple match scenarios

🛠️ Testing Steps

cargo make check

OR run the test suite: cargo test