Simplify trace eraser - unset HISTFILE to prevent re-adding

Changes:
- Remove complex history -d loop (unreliable)
- Clean file directly with grep -Ev only
- Clear current session with history -c
- Unset HISTFILE to prevent session from writing on exit
- Disable histappend for current session

Issue:
- Complex history manipulation was unreliable
- Current session kept re-adding commands on exit
- history -w then grep -Ev was conflicting

Solution:
- Just clean the file, period
- Unset HISTFILE so current session won't write anything
- Tell user to exit immediately and start fresh shell

Tested:
✓ File cleaned with grep -Ev
✓ HISTFILE unset prevents writing on exit

tools/erase-toolkit-traces.sh

@@ -122,60 +122,36 @@ if [ "$CLEAN_HISTORY" = true ] && [ -f ~/.bash_history ]; then
     echo ""
     echo "→ Final cleanup: Removing bash history..."
 
-    # Disable history recording for this session to prevent re-adding commands
+    # Disable history recording AND appending for this session
     set +o history
+    shopt -u histappend 2>/dev/null || true
 
-    # Clean in-memory history first using history -d (most reliable method)
-    echo "  → Cleaning in-memory history..."
+    echo "  → Cleaning history file..."
     GREP_PATTERN="git\.mull\.lol|linux-server-management-toolkit|server-toolkit|launcher\.sh|erase-toolkit-traces"
 
-    # Get list of history entry numbers to delete (reverse order to maintain numbering)
-    entries_to_delete=$(history | grep -E "$GREP_PATTERN" | awk '{print $1}' | sort -rn)
-    entries_count=$(echo "$entries_to_delete" | grep -c '^' 2>/dev/null || echo 0)
-
-    # Delete each matching entry from in-memory history
-    for entry_num in $entries_to_delete; do
-        history -d "$entry_num" 2>/dev/null || true
-    done
-
-    echo "  ✓ Removed $entries_count toolkit-related entries from in-memory history"
-
-    # Also remove any 'history' commands that might show investigation
-    echo "  → Removing history command traces..."
-    history_entries=$(history | grep -E '^\s*[0-9]+\s+.*history' | awk '{print $1}' | sort -rn)
-    history_count=$(echo "$history_entries" | grep -c '^' 2>/dev/null || echo 0)
-
-    for entry_num in $history_entries; do
-        history -d "$entry_num" 2>/dev/null || true
-    done
-
-    if [ "$history_count" -gt 0 ]; then
-        echo "  ✓ Removed $history_count history command entries"
-    fi
-
-    # Write cleaned in-memory history back to file
-    history -w
-
-    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..."
+    # Clean the history file directly
     if [ -f ~/.bash_history ]; then
         cp ~/.bash_history ~/.bash_history.bak.$$
+        lines_before=$(wc -l < ~/.bash_history.bak.$$ 2>/dev/null || echo 0)
         grep -Ev "$GREP_PATTERN" ~/.bash_history.bak.$$ > ~/.bash_history 2>/dev/null || true
+        lines_after=$(wc -l < ~/.bash_history 2>/dev/null || echo 0)
+        lines_removed=$((lines_before - lines_after))
         rm -f ~/.bash_history.bak.$$
-        echo "  ✓ History file cleaned"
+        echo "  ✓ Removed $lines_removed entries from history file"
     fi
 
-    # Reload cleaned history into current session to prevent re-adding on exit
-    echo "  → Reloading cleaned history into current session..."
+    # Clear current session's history completely to prevent re-adding on exit
+    echo "  → Clearing current session history..."
     history -c
-    history -r
 
-    echo "  ✓ In-memory history reloaded from cleaned file"
+    # Unset HISTFILE to prevent this session from writing on exit
+    unset HISTFILE
+
+    echo "  ✓ Current session history cleared and disabled"
     echo ""
-    echo "NOTE: For complete cleanup, run 'exec bash' to start a fresh shell."
-    echo "      This prevents any lingering history from being re-saved."
+    echo -e "${YELLOW}IMPORTANT: Exit this shell immediately after cleanup${NC}"
+    echo "Type: exit"
+    echo "Then start a fresh shell to see cleaned history."
 fi
 
 # Offer to remove the entire toolkit (AFTER history cleaning)