[FEATURE] Add real-time call trace visualization for debugging multi-agent workflows #20168

Description

When working with complex multi-agent workflows involving LLM calls, tool executions, and OMO agents, it's difficult to visualize the timing and flow of calls between components. A real-time trace visualization would help developers understand and debug these workflows.

Problem Statement

Currently, there's no way to see:

• Which LLM calls are being made and their duration
• Which tools are being executed and their status
• How OMO agents are being spawned and their lifecycle
• The relationship between different calls in a message

Proposed Solution

Add a CallTraceBar component to the TUI session view that:

• Shows real-time call traces from OC, OMO, and LLM sources
• Displays trace details including duration, timing, and expandable input/output summaries
• Can be toggled with a keybind (e.g., <leader>v)
• Helps visualize complex multi-agent workflows

Benefits

• Easier debugging of multi-agent workflows
• Better understanding of system behavior
• Performance analysis of LLM and tool calls
• Improved developer experience

Additional Context

This would be particularly useful for developers building custom agents or debugging complex tool chains.