SSH MCP Server

# Feature: Command Cancellation ## Feature Description Source-specific command cancellation system allowing browser users (Ctrl-C) and MCP clients (cancel command) to terminate their respective commands without affecting the other source. ## Technical Architecture ### Cancellation Sources - **Browser**: Existing Ctrl-C via `sendTerminalSignal` - **MCP Client**: New `ssh_cancel_command` tool ### Gating Integration - Cancellation respects command source ownership - Browser can only cancel browser-initiated commands - MCP can only cancel MCP-initiated commands ## Story Implementation Order - [ ] 01_Story_BrowserCommandCancellation - [ ] 02_Story_MCPCommandCancellation - [ ] 03_Story_SourceSpecificCancellation ## Success Criteria - ⏸️ **Source Isolation**: Each source can only cancel own commands - ✅ **Gate Release**: Cancellation releases gatekeeper for other source - 🔧 **Existing Integration**: Browser Ctrl-C continues working - ⚙️ **MCP Tool**: New cancel command available for Claude Code