chore: bootstrap Godot quality tools

tools/fix_format.sh

@@ -8,14 +8,16 @@ cd "$ROOT"
 
 # detect gdformat
 FMT=""
-if command -v gdformat &>/dev/null; then
+if [[ -x "$ROOT/.venv/bin/gdformat" ]]; then
+  FMT="$ROOT/.venv/bin/gdformat"
+elif command -v gdformat &>/dev/null; then
   FMT="gdformat"
 elif python -m gdtoolkit.formatter --help &>/dev/null 2>&1; then
   FMT="python -m gdtoolkit.formatter"
 fi
 
 if [[ -z "$FMT" ]]; then
-  echo "ERROR: gdformat not found. Install: pip install gdtoolkit"
+  echo "ERROR: gdformat not found. Install requirements-dev.txt; see docs/local_quality_gate.md."
   exit 1
 fi