aish supports shell prompts

[jexShain]

Summary

• Problem: aish supports shell prompts
• Changes:
• Related Issue: [Feature]: add shell prompts script #65

Modify this configuration file to turn on this function
~/.config/aish/config.yaml

enable_scripts: true

Change Type

• Bug fix
• Feature
• Refactor
• Docs
• Other

Scope

• Core shell / PTY
• AI agent / LLM
• Skills / Tools
• Security
• Configuration
• CLI / Interface
• Packaging / Installation
• CI/CD
• Documentation

User-visible Changes

Compatibility

• Backward compatible? (Yes/No)
• Config changes? (Yes/No - if yes, describe migration)

Testing

 :~/n/x/g/aish|main⚡*?➜➜ make lint                                                                                    
🔍 Running linting...                                                                                                  
uv run --group dev ruff check src/ tests/                                                                              
All checks passed!                                                                                                     
uv run --group dev mypy src/                                                                                           
src/aish/env_manager.py:21: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                     
src/aish/prompts.py:16: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                         
src/aish/interruption.py:71: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/interruption.py:75: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/interruption.py:79: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/interruption.py:80: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/interruption.py:83: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/interruption.py:86: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                                                    
src/aish/shell_enhanced/shell_pty_executor.py:228: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                              
src/aish/shell_enhanced/shell_pty_executor.py:229: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]                                                              
src/aish/shell_enhanced/shell_pty_executor.py:272: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]
src/aish/skills/manager.py:66: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]
src/aish/skills/manager.py:67: note: By default the bodies of untyped functions are not checked, consider using --check-untyped-defs  [annotation-unchecked]
Success: no issues found in 110 source files

Checklist

• Code follows project style
• Tests added if needed
• Documentation updated if needed

[F16shen]

这轮 review 里我主要有几项阻塞点：

1. enable_scripts 目前是默认开启并且会把旧配置自动迁移成开启状态，这会让现有用户无感切到新的 prompt/script 路径，和 PR 描述里的手动启用预期不一致。
2. 脚本 hot reload 的启动时序有问题，首次启动时如果 scripts 目录还不存在，watcher 会直接退出，默认 prompt 模板也无法在当前会话里生效。
3. prompt 失败态依赖进程环境里的 ?，但当前 shell 没有看到有地方可靠维护它，这会让 prompt 状态不可信。
4. handle_script_call() 里 OLDPWD 会被写成新目录而不是旧目录。
5. 脚本调用优先级高于普通命令，会直接遮蔽同名系统命令。
6. ScriptExecutor 当前是按行解释脚本，和用户对 shell 脚本语义的预期差异很大，现有测试也还没有覆盖这些高风险场景。

我已经把这些点分别挂到了对应代码行上，建议先把这些基础语义和兼容性问题收敛之后再继续推进。