refactor: 重构目录结构以支持 i18n

创建 'i18n' 目录以存放多语言内容。将所有现有的中文内容（文档、提示词、技能、README）移动到 'i18n/zh/' 中。添加了新的根 README 作为语言入口，并为英文（'en'）翻译创建了占位符结构。

skills/twscrape/references/installation.md

@@ -1,66 +0,0 @@
-# Installation
-
-## Standard Installation
-
-```bash
-pip install twscrape
-```
-
-## Development Version
-
-Install the latest development version directly from GitHub:
-
-```bash
-pip install git+https://github.com/vladkens/twscrape.git
-```
-
-## Requirements
-
-- Python 3.7+
-- asyncio support
-- Internet connection for Twitter/X access
-
-## Dependencies
-
-The library automatically installs required dependencies:
-- `httpx` - Async HTTP client
-- `aiosqlite` - Async SQLite database
-- Additional dependencies as specified in setup.py
-
-## Verification
-
-Verify installation:
-
-```bash
-# Check CLI is available
-twscrape --help
-
-# Check Python import works
-python -c "from twscrape import API; print('OK')"
-```
-
-## Upgrading
-
-```bash
-pip install --upgrade twscrape
-```
-
-## Uninstallation
-
-```bash
-pip uninstall twscrape
-```
-
-## Database Location
-
-By default, twscrape creates `accounts.db` in your current working directory. You can specify a custom location:
-
-```python
-api = API("path/to/custom.db")
-```
-
-Or via CLI:
-
-```bash
-twscrape --db path/to/custom.db <command>
-```