fix: import is_test_mode from autoconf instead of autofit

PyAutoArray does not depend on autofit. The previous import caused
CI failures (ModuleNotFoundError). Also add dependency graph to
CLAUDE.md to prevent this class of error.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: 2 people

CLAUDE.md

@@ -2,6 +2,13 @@
 
 This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
 
+## Dependency Graph
+
+PyAutoArray depends on **autoconf** (shared configuration and utilities).
+PyAutoArray does **NOT** depend on PyAutoFit, PyAutoGalaxy, or PyAutoLens.
+Never import from `autofit`, `autogalaxy`, or `autolens` in this repo.
+Shared utilities (e.g. `test_mode`, `jax_wrapper`) belong in autoconf.
+
 ## Commands
 
 ### Install

autoarray/inversion/mesh/image_mesh/hilbert.py

@@ -12,7 +12,7 @@
 from autoarray.structures.grids.irregular_2d import Grid2DIrregular
 
 from autoarray import exc
-from autofit.non_linear.test_mode import is_test_mode
+from autoconf.test_mode import is_test_mode
 
 
 def gilbert2d(width, height):