docs: 重构为双语文档结构，添加人设图机制

- 拆分为 docs/(CN) 和 docs_en/(EN) 两个文件夹
- 主 README 索引对应语言文档
- 新增 persona.md (人设图机制详细说明)
- 文件重命名为英文名

docs_en/README.md

@@ -0,0 +1,29 @@
+# TrulyMEM Documentation
+
+Welcome to the TrulyMEM project documentation.
+
+## Documentation Index
+
+| Document | Content |
+|----------|---------|
+| [architecture.md](architecture.md) | System architecture and technical design |
+| [quick_start.md](quick_start.md) | Complete startup guide and configuration |
+| [memory.md](memory.md) | Internal memory working mechanism |
+| [persona.md](persona.md) | Persona Graph mechanism |
+| [working_memory.md](working_memory.md) | Continuous task handling mechanism |
+| [api.md](api.md) | Backend API reference (for extension development) |
+| [prompts.md](prompts.md) | Prompt management module |
+
+## Project Introduction
+
+TrulyMEM (TrueHumanMEM) is a graph-based memory system that gives AI long-term memory capabilities, allowing AI to remember, recall, and manage information like humans.
+
+## Core Features
+
+- **Long-term Memory**: SQLite embedded graph database, out-of-the-box
+- **Persona Graph**: Role-playing and character settings support
+- **Working Memory Chain**: Task tracking for conversation continuity
+- **TUI & Backend Separation**: Multi-threaded Queue communication
+- **Keyboard-driven TUI**: Full keyboard operation, no mouse required
+- **Cross-platform**: Windows / Linux / macOS
+- **Standalone Deployment**: Packaged as executable