[FEATURE]: Background Tasks Manager #9714

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Describe the enhancement you want to request

✨ Key Features

🔧 Core Task Manager (packages/opencode/src/task/)

• TaskManager with full lifecycle operations:
  • ✅ create() - Spawn new background processes
  • 📋 list() - Get all running tasks
  • 🔍 get() - Retrieve specific task info
  • ⚡ kill() - Terminate processes
  • 📖 read() - Read task output (full or partial)
  • 📜 tail() - Stream recent output
  • ⌨️ input() - Send input to running processes
  • 🔄 adopt() - Migrate foreground processes to background
• Persistence Layer (.opencode/tasks/{taskId}.json):
  • 💾 Tasks survive session restarts
  • 🔌 Auto-reconnect to running processes by PID
  • 📊 State tracking and recovery
• Event Bus System:
  • 🎉 task:created - New task spawned
  • 📝 task:output - Output received
  • ✔️ task:completed - Task finished
  • ❌ task:killed - Task terminated

🤖 Process Query Tool (packages/opencode/src/tool/process-query.ts)

New LLM tool that enables Claude to:

• 📋 List all background tasks
• ✅ Check task status
• 📖 Read full or partial output
• 🔍 Search for patterns in task logs
• 🎯 Resolve tasks by ID, "last" keyword, or description match

🎨 User Interface Components

Background Tasks Modal (ctrl+p > "Background tasks"):

• 📊 View all running background tasks
• 📈 Real-time output streaming
• ⚡ Kill tasks directly from UI
• 🔄 Auto-refresh with live updates

Process Controls:

• 🔵 [bg] button - Migrate running processes to background
• 🔴 [kill] button - Terminate running processes
• 🎮 Available for both Bash commands and shell commands (! prefix)

🛠️ Enhanced Bash Tool

• ✅ run_in_background parameter for spawning background tasks
• 🔄 Foreground process registry for tracking
• 🎯 Support for process migration while running
• 🧹 Optimized latency with fire-and-forget persistence

📊 Implementation Stats

• Files Changed: 20 files
• Lines Added: ~4,878 lines
• Test Coverage: 46 comprehensive tests
  • 29 tests for TaskManager core
  • 17 tests for foreground process management

🎬 Demo

(https://x.com/avillagran/status/2013709707563708491/video/1)

🔍 Technical Details

Architecture:

1. Task Layer - Process management and lifecycle
2. Persistence Layer - State storage and recovery
3. Transport Layer - RPC handlers for TUI communication
4. UI Layer - React components for user interaction

Key Design Decisions:

• 🚀 Fire-and-forget persistence to minimize migration latency
• 🔄 PID-based reconnection for session recovery
• 🎯 Unified interface for both foreground and background processes
• 📝 Clean logging using Log utility instead of console

🧪 Testing

Comprehensive test suite covering:

• ✅ Task creation and lifecycle
• ✅ Output streaming and reading
• ✅ Process termination
• ✅ Session recovery
• ✅ Foreground to background migration
• ✅ Error handling and edge cases

📚 Use Cases

• 🏗️ Long-running builds (webpack, vite, etc.)
• 🧪 Test watchers and development servers
• 📦 Package installations
• 🔍 Log monitoring and analysis
• 🤖 Any command that needs to run while working on other tasks