Default repo clone branch to main for training notebooks and HF script.

Colab and hf_run_train_grpo now clone main; override with HF_REPO_BRANCH if needed.

training/hf_run_train_grpo.sh

@@ -11,7 +11,7 @@ IMAGE="${HF_JOB_IMAGE:-pytorch/pytorch:2.5.1-cuda12.4-cudnn9-runtime}"
 FLAVOR="${HF_JOB_FLAVOR:-l4x1}"
 TIMEOUT="${HF_JOB_TIMEOUT:-8h}"
 REPO_URL="${HF_REPO_URL:-https://github.com/VaibhavKhandare/viral-posts-env.git}"
-REPO_BRANCH="${HF_REPO_BRANCH:-hack1}"
+REPO_BRANCH="${HF_REPO_BRANCH:-main}"
 
 exec hf jobs run \
   --flavor "$FLAVOR" \

training/train_grpo.ipynb

@@ -50,7 +50,7 @@
         "import subprocess\n",
         "from pathlib import Path\n",
         "\n",
-        "REPO_BRANCH = \"hack1\"\n",
+        "REPO_BRANCH = \"main\"\n",
         "REPO_URL = \"https://github.com/VaibhavKhandare/viral-posts-env.git\"\n",
         "COLAB_REPO = Path(\"/content/viral-posts-env\")\n",
         "\n",
@@ -170,7 +170,7 @@
         "# Hard stop if stale repo/code is loaded\n",
         "assert TASK_HORIZON == 15, (\n",
         "    f\"Expected TASK_HORIZON=15, got {TASK_HORIZON}. \"\n",
-        "    \"Restart runtime and run from Cell 1 again (clean clone on hack1).\"\n",
+        "    \"Restart runtime and run from Cell 1 again (clean clone on main).\"\n",
         ")\n",
         "\n",
         "# Same sanity as syntax_only.ipynb (kernel parses modern Python)\n",

training/train_grpo_smoke.ipynb

@@ -35,7 +35,7 @@
         "import subprocess\n",
         "from pathlib import Path\n",
         "\n",
-        "REPO_BRANCH = \"hack1\"\n",
+        "REPO_BRANCH = \"main\"\n",
         "REPO_URL = \"https://github.com/VaibhavKhandare/viral-posts-env.git\"\n",
         "COLAB_REPO = Path(\"/content/viral-posts-env\")\n",
         "\n",