Document log message formatting improvement as backlog issue

.github/BACKLOG_ISSUE_LOG_MESSAGE_FORMATTING.md

@@ -0,0 +1,38 @@
+# Backlog Issue: Improve Log Message String Formatting for Clarity
+
+## Description
+The log message for whack success in `whack-a-mole/backend/app.py` (lines 518-519) uses string continuation where the space separator appears at the beginning of the second string, making it less obvious that proper spacing exists.
+
+## Current Code
+```python
+print(
+    f"[Thread-{thread_name}] Whack success!"
+    f" Hole {hole}, Time: {result['reaction_time']:.3f}s"
+)
+```
+
+## Suggested Improvement
+Move the space to the end of the first string for better clarity:
+```python
+print(
+    f"[Thread-{thread_name}] Whack success! "
+    f"Hole {hole}, Time: {result['reaction_time']:.3f}s"
+)
+```
+
+## Location
+- **File**: `whack-a-mole/backend/app.py`
+- **Lines**: 518-519
+- **Commit Reference**: 2f38f6fac1f58668cbb86df2875738737df2725e
+
+## Priority
+Low - This is a code style/readability improvement. The current code functions correctly and produces the expected output with proper spacing.
+
+## Labels
+- `good first issue`
+- `code-quality`
+- `python`
+
+## Origin
+This issue was identified during code review on PR #4:
+https://github.com/IanDTM/copilot-hack/pull/4#discussion_r2655765837