Add file-based history cleaning to trace eraser

Changes:
- Clean ~/.bash_history file directly after in-memory cleaning
- Handles commands from other terminal sessions
- Ensures complete cleanup even if history not yet written

Issue:
- history -d only cleans current session's in-memory history
- Commands from other sessions remain in ~/.bash_history file
- User's curl command persisted because it was from different session

Solution:
- After history -w, also grep -Ev on the history file
- Removes toolkit commands regardless of which session added them

Tested:
✓ Pattern matches user's curl command format
✓ Extracts correct entry numbers

tools/erase-toolkit-traces.sh

@@ -181,6 +181,15 @@ if [ "$CLEAN_HISTORY" = true ] && [ -f ~/.bash_history ]; then
 
     echo "  ✓ Cleaned history written to file"
 
+    # Also clean the history file directly (in case commands are from other sessions)
+    echo "  → Cleaning history file for commands from other sessions..."
+    if [ -f ~/.bash_history ]; then
+        cp ~/.bash_history ~/.bash_history.bak.$$
+        grep -Ev "$GREP_PATTERN" ~/.bash_history.bak.$$ > ~/.bash_history 2>/dev/null || true
+        rm -f ~/.bash_history.bak.$$
+        echo "  ✓ History file cleaned"
+    fi
+
     echo "  ✓ In-memory history reloaded from cleaned file"
     echo ""
     echo "NOTE: Other active terminal sessions may still have old history in memory."