feat: 新增现代化命令替代功能 v0.2.0

🎯 主要功能:
- 智能检测系统中已安装的现代化命令行工具
- 支持 44 种默认命令映射 (ls→eza, cat→bat, find→fd 等)
- 灵活的环境变量配置系统
- AI 提示词集成，优先推荐现代化工具
- 完整的配置状态显示

⚙️ 配置方式:
- 环境变量: AI_SHELL_MODERN_COMMANDS="ls:eza,cat:bat"
- .env 文件配置支持
- 动态配置检测和合并

🔧 技术实现:
- 新增 get_modern_commands() 配置管理
- 新增 get_available_modern_commands() 系统检测
- 新增 generate_modern_commands_prompt() 提示词生成
- 更新 AI agent 系统提示词
- 完善配置显示和测试脚本

📊 支持的现代化工具:
文件操作: eza, bat, fd, tree
文本处理: rg, sd, choose, delta
系统监控: procs, htop, ncdu, duf
网络工具: gping, httpie, aria2c
编辑器: nvim, micro
其他: zoxide, trash, ouch, pnpm

ai_shell/agent.py

@@ -6,42 +6,48 @@ from textwrap import dedent
 from pydantic_ai import Agent
 from pydantic_ai.models.openai import OpenAIModel
 
-from .config import get_model, setup_environment
+from .config import get_model, setup_environment, generate_modern_commands_prompt
 from .models import Answer
 
-# System prompt for the AI agent
-SYSTEM_PROMPT = dedent(
-    """\
-    You are a professional developer specializing in shell commands.
-    Your task is to generate the correct shell commands based on the 
-    user's request.
+def create_system_prompt() -> str:
+    """Create system prompt with modern commands preferences"""
+    base_prompt = dedent(
+        """\
+        You are a professional developer specializing in shell commands.
+        Your task is to generate the correct shell commands based on the
+        user's request.
 
-    IMPORTANT: ALWAYS USE THE SAME LANGUAGE AS THE USER PROMPT IN 
-    YOUR RESPONSE.
+        IMPORTANT: ALWAYS USE THE SAME LANGUAGE AS THE USER PROMPT IN
+        YOUR RESPONSE.
 
-     Process:
+        Process:
 
-    1. Think Aloud: Use the `think` function to explain your reasoning. 
-    Justify why you chose a particular command, considering efficiency,
-    safety, and best practices.
+        1. Think Aloud: Use the `think` function to explain your reasoning.
+        Justify why you chose a particular command, considering efficiency,
+        safety, and best practices.
 
-    2. Provide the Final Command: Use the `answer` function to present
-    the final shell command concisely.
-"""
-)
+        2. Provide the Final Command: Use the `answer` function to present
+        the final shell command concisely.
+        """
+    )
+
+    # Add modern commands preferences
+    modern_commands_prompt = generate_modern_commands_prompt()
+
+    return base_prompt + modern_commands_prompt
 
 def create_agent() -> Agent:
     """Create and configure the AI agent"""
     # Setup environment variables
     setup_environment()
-    
+
     # Create OpenAI compatible model
     model = OpenAIModel(get_model())
-    
-    # Create agent
+
+    # Create agent with dynamic system prompt
     agent = Agent(
         model=model,
-        system_prompt=SYSTEM_PROMPT,
+        system_prompt=create_system_prompt(),
         output_type=Answer,
     )