feat: Bash 工具支持实时流式输出

Problem

When executing long-running Bash commands in Claude Code CLI, there's no output until the command completes. Users have no way to know if the command is stuck or just running slowly.

Current Behavior

User: run npm install
(Nothing happens for 30 seconds...)
bot: ✅ Done

The user stares at a blank screen with no feedback.

Desired Behavior

Real-time streaming output from Bash commands:

User: run npm install
bot: [0s] Starting npm install...
bot: [5s] added 50 packages
bot: [10s] added 100 packages
bot: [15s] added 150 packages
bot: [20s] ✅ Done

Why This Matters

1. User Experience - Users can't tell if the tool is working or frozen
2. Trust - No feedback = no confidence the task is progressing
3. Productivity - Users waste time waiting and wondering

Suggested Implementation

• Stream stdout/stderr in real-time as it's produced
• Show elapsed time and progress indicators
• Allow user to interrupt (Ctrl+C) if command seems stuck

Environment

• Claude Code CLI v2.1.152
• Platform: Windows 11