docs: add Russian README and a Windows start.bat launcher

- README_RU.md: full Russian translation, linked from README.md
- start.bat: one-click setup + launch for Windows. Finds Python 3.10+,
  creates the venv, installs PyTorch (CUDA or CPU) and ACE-Step, checks
  the GPU, then starts the web UI. Flags: --lowvram, --cpu, --share,
  --port, --device, --listen, --reinstall, --update, --setup, --help.
- Both READMEs document the launcher.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

README.md

@@ -10,6 +10,10 @@
     <a href="https://ace-step.github.io/ace-step-v1.5.github.io/">ACE-Step v1.5</a>
 </p>
 
+<p align="center">
+    <b>Language:</b> <b>English</b> | <a href="./README_RU.md">Русский</a>
+</p>
+
 <p align="center">
     <img src="./assets/orgnization_logos.png" width="100%" alt="StepFun Logo">
 </p>
@@ -18,6 +22,7 @@
 
 - [✨ Features](#-features)
 - [📦 Installation](#-installation)
+- [⚡ Quick Start (Windows)](#-quick-start-windows)
 - [🚀 Usage](#-usage)
 - [📱 User Interface Guide](#-user-interface-guide)
 - [🔨 Train](#-train)
@@ -258,6 +263,42 @@ pip install -e .
 The ACE-Step application is now installed. The GUI works on Windows, macOS, and Linux. For instructions on how to run it, please see the [Usage](#-usage) section.
 
 
+## ⚡ Quick Start (Windows)
+
+This repository ships with [`start.bat`](./start.bat), which does everything for you: checks Python, creates the virtual environment, installs PyTorch with CUDA support, installs ACE-Step, and launches the web UI.
+
+Just double-click `start.bat`, or run it from a command prompt:
+
+```bat
+start.bat
+```
+
+The first run takes a few minutes (roughly 3 GB of packages are downloaded). Model weights (~8 GB) are fetched automatically on the first generation. Later runs start immediately.
+
+### Script flags
+
+| Flag | What it does |
+| --- | --- |
+| `--lowvram` | Low-VRAM mode (~8 GB): enables `--cpu_offload`, `--overlapped_decode` and `--torch_compile`, and installs `triton-windows` |
+| `--cpu` | Run on CPU without CUDA (very slow, but works without an NVIDIA GPU) |
+| `--share` | Create a public Gradio link |
+| `--port <N>` | Web UI port (default 7865) |
+| `--device <N>` | GPU index (default 0) |
+| `--listen` | Bind to `0.0.0.0` so other devices on the LAN can connect |
+| `--reinstall` | Recreate the virtual environment from scratch |
+| `--update` | Update dependencies in the existing environment |
+| `--setup` | Install only, do not launch |
+| `--help` | Show usage |
+
+Flags can be combined, for example:
+
+```bat
+start.bat --lowvram --listen --port 7870
+```
+
+Defaults (port, GPU index, checkpoint path) live in the settings block at the top of `start.bat`.
+
+
 ## 🚀 Usage
 
 ![Demo Interface](assets/demo_interface.png)