Change bash history cleanup to only remove last 10 entries

Reduced from 50 to 10 entries for more targeted cleanup.

Changes:
• Only removes last 10 bash history entries
• More conservative approach
• Still covers toolkit download and usage
• Less impact on normal command history

Tested and confirmed working.

tools/erase-toolkit-traces.sh

@@ -145,16 +145,16 @@ if [ "$CLEAN_HISTORY" = true ] && [ -f ~/.bash_history ]; then
     echo ""
     echo "→ Final cleanup: Removing bash history..."
 
-    # Remove last 50 lines from history file
+    # Remove last 10 lines from history file (covers toolkit download/usage)
     total_lines=$(wc -l < ~/.bash_history)
-    if [ "$total_lines" -gt 50 ]; then
-        lines_to_keep=$((total_lines - 50))
+    if [ "$total_lines" -gt 10 ]; then
+        lines_to_keep=$((total_lines - 10))
         head -n "$lines_to_keep" ~/.bash_history > ~/.bash_history.tmp
         mv ~/.bash_history.tmp ~/.bash_history
-        echo "  ✓ Removed last 50 history entries"
+        echo "  ✓ Removed last 10 history entries"
     else
         > ~/.bash_history
-        echo "  ✓ Cleared entire history (had < 50 entries)"
+        echo "  ✓ Cleared entire history (had < 10 entries)"
     fi
 
     # Clear in-memory history and write clean file