Environment setup + train loop (#5)

Mujoco environment setup (vectorized on GPU) + training loop + simulate script

README.md

@@ -0,0 +1,17 @@
+# Brittle Star
+
+## Usage
+
+### UV
+
+To set up the UV module, you can run the following command:
+
+```bash
+uv sync --frozen
+```
+
+example command:
+
+```bash
+uv run src/train.py --model_name my_model --epochs 50 --batch_size 32
+```