Simplify notebook setup

docs/tutorial/train.ipynb

@@ -22,7 +22,8 @@
     "\n",
     "Use Python 3.12 or 3.13 and install this checkout with `uv pip install --editable '.[notebooks]'`.\n",
     "See **Run notebooks locally** in the repository README for the kernel, execution order,\n",
-    "and full-data options. Generated artifacts stay under `.cache/notebooks/`.\n"
+    "and full-data options. Run related notebooks from the same working directory\n",
+    "to share the default `.cache/` model store and `tracing_database.json` database.\n"
    ],
    "metadata": {}
   },
@@ -32,23 +33,7 @@
    "metadata": {},
    "execution_count": null,
    "source": [
-    "import os\n",
-    "import sys\n",
-    "from pathlib import Path\n",
-    "\n",
-    "# Works when opened from the repository root or any notebook directory.\n",
-    "_start = Path(globals().get(\"__file__\", Path.cwd())).resolve()\n",
-    "ROOT = next(\n",
-    "    p\n",
-    "    for p in [_start, *_start.parents]\n",
-    "    if (p / \"pyproject.toml\").is_file() and (p / \"great_ai\").is_dir()\n",
-    ")\n",
-    "sys.path.insert(0, str(ROOT / \"docs\"))\n",
-    "from notebook_support import setup_notebook, mag_lines\n",
-    "\n",
-    "FULL_RUN = os.environ.get(\"GREAT_AI_NOTEBOOK_FULL\") == \"1\"\n",
-    "WORK_DIR = setup_notebook(ROOT, \"tutorial\")\n",
-    "DATA_DIR = ROOT / \"docs/tutorial/data\""
+    "from docs.notebook_support import DATA_DIR, FULL_RUN, mag_lines"
    ],
    "outputs": []
   },