feat: update workspace paths and enhance gitignore

- Updated stablediffusion crate path from "../stable-diffusion-burn" to "./crates/stable-diffusion-burn" for proper workspace resolution
- Enhanced .gitignore to include generated model files (.mpk, .pt, .bin, .safetensors, .ckpt) and user_data directory
- Added Cargo.lock to gitignore with appropriate comment
- Reorganized IDE files section in gitignore for better clarity
- Added newline at end of file for proper formatting

crates/stable-diffusion-burn/burn-crates/burn-backend-tests/tests/cubecl/unary.rs

@@ -0,0 +1,24 @@
+use super::*;
+use burn_tensor::Tensor;
+
+#[test]
+fn tanh_should_not_have_numerical_bugs_on_macos() {
+    fn tanh_one_value(input: f32) -> f32 {
+        let tensor = Tensor::<TestBackend, 1>::ones([1], &Default::default()) * input;
+        let output = tensor.tanh().into_primitive();
+        Tensor::<TestBackend, 1>::from_primitive(output)
+            .into_data()
+            .as_slice()
+            .unwrap()[0]
+    }
+
+    let ok = tanh_one_value(43.0); // metal tanh gives 1.0 which is the right answer
+    let zero = tanh_one_value(44.0); // metal tanh gives zero when within 43.67..44.36
+    let nan = tanh_one_value(45.0); // metal tanh gives nan when over 44.36
+    let neg = tanh_one_value(-45.0); //  metal works correctly here
+
+    assert!(!ok.is_nan() && ok == 1.0);
+    assert!(!zero.is_nan() && zero == 1.0);
+    assert!(!nan.is_nan() && nan == 1.0);
+    assert!(!neg.is_nan() && neg == -1.0);
+}