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-no-std-tests/Cargo.toml

@@ -0,0 +1,32 @@
+[package]
+authors = [
+  "nathanielsimard <nathaniel.simard.42@gmail.com>",
+  "Dilshod Tadjibaev (@antimora)",
+]
+edition.workspace = true
+license.workspace = true
+name = "burn-no-std-tests"
+readme.workspace = true
+repository = "https://github.com/tracel-ai/burn/tree/main/crates/burn-no-std-tests"
+version.workspace = true
+
+[lints]
+workspace = true
+
+[features]
+default = []
+
+tracing = [
+    "burn/tracing",
+    "burn-ndarray/tracing",
+    "burn-store/tracing",
+]
+
+[dependencies]
+
+# ** Please make sure all dependencies support no_std **
+
+burn = { path = "../burn", version = "=0.21.0-pre.2", default-features = false }
+burn-ndarray = { path = "../burn-ndarray", version = "=0.21.0-pre.2", default-features = false }
+
+burn-store = { path = "../burn-store", version = "=0.21.0-pre.2", default-features = false, features = ["safetensors", "burnpack"]}