docs: add Windows installation guide for SDK (#187)

* Add Windows installation guide for opengradient package

Provides a step-by-step guide for installing the opengradient package on Windows using WSL, including common errors and their fixes.

Signed-off-by: Saiful-15931 <tsbsaifulgaming@gmail.com>

* Revise Windows installation note in README

Updated installation note for Windows users to reference guide.

Signed-off-by: Saiful-15931 <tsbsaifulgaming@gmail.com>

* Update Windows installation guide formatting

Reformatted installation steps for clarity and consistency.

Signed-off-by: Saiful-15931 <tsbsaifulgaming@gmail.com>

* Refine Windows installation guide for opengradient

Updated installation steps for clarity and added missing commands.

Signed-off-by: Saiful-15931 <tsbsaifulgaming@gmail.com>

---------

Signed-off-by: Saiful-15931 <tsbsaifulgaming@gmail.com>

Author: Saiful-15931

README.md

@@ -24,7 +24,7 @@ OpenGradient enables developers to build AI applications with verifiable executi
 pip install opengradient
 ```
 
-**Note**: Windows users should temporarily enable WSL during installation (fix in progress).
+**Note**: > **Windows users:** See the [Windows Installation Guide](./WINDOWS_INSTALL.md) for step-by-step setup instructions.
 
 ## Network Architecture
 

WINDOWS_INSTALL.md

@@ -0,0 +1,36 @@
+# Windows Installation Guide
+
+The `opengradient` package requires a C compiler
+to build its native dependencies. Windows does not
+have one by default.
+
+## Step 1 — Enable WSL
+
+Open PowerShell as Administrator and run:
+
+    wsl --install
+
+Restart your PC when prompted.
+
+## Step 2 — Install Python and uv inside WSL
+
+Open the Ubuntu app and run:
+
+    sudo apt update && sudo apt install -y python3 curl
+    curl -LsSf https://astral.sh/uv/install.sh | sh
+    source $HOME/.local/bin/env
+
+## Step 3 — Install SDK
+
+    uv add opengradient
+
+## Step 4 — Verify
+
+    uv run python3 -c "import opengradient; print('Ready!')"
+
+## Common Errors
+
+- Visual C++ 14.0 required → Use WSL instead
+- wsl: command not found → Update Windows 10 to Build 19041+
+- WSL stuck → Enable Virtualization in BIOS
+- uv: command not found → Run: source $HOME/.local/bin/env