add docs (#201)

add docs.

docs/source_en/GetStarted/Installation.md

@@ -0,0 +1,24 @@
+# Installation
+
+## From Source
+
+1. Clone the source repository:
+
+    ```bash
+    git clone https://github.com/modelscope/DiffSynth-Studio.git
+    ```
+
+2. Navigate to the project directory and install:
+
+    ```bash
+    cd DiffSynth-Studio
+    pip install -e .
+    ```
+
+## From PyPI
+
+Install directly via PyPI:
+
+```bash
+pip install diffsynth
+```