Color-Coded Task vs. Execution Output

### Describe the feature or problem you'd like to solve

Add visual differentiation between task definitions and execution output in Copilot CLI

### Proposed solution

Problem Statement
When Copilot CLI generates and executes multi-step sequences (see image), users cannot quickly distinguish between:

- Task definitions: The instructions/commands Copilot is creating or about to execute
- Execution feedback: The actual CLI output and results from running those commands

This forces cognitive overhead—users must read sequentially and re-parse context, slowing comprehension and increasing the chance of missing failures or unexpected behavior.

Current Behavior
All output (task prompts, execution logs, status messages) renders in the same color scheme, creating visual ambiguity.
Desired Behavior
Implement a color-coding scheme that immediately signals intent:

- Task/Instruction layer (white or bright): "Here's what I'm about to do"
- Execution layer (grey or muted): "Here's what actually happened when I ran it"
- Status/warnings (optional yellow/red): Failures or important flags

Reference Implementation
Claude Code already solves this elegantly

- Grey text for task execution progress
- White/bright text for actionable TODOs and CLI comments
- Scanning the output is ~40% faster because your eye separates concerns immediately

Why This Matters
For developer workflows:

- Error detection: Grey execution output makes failures pop when they appear
- Auditability: You can quickly verify what Copilot planned vs. what actually ran
- Cognitive bandwidth: Frees mental cycles for decision-making instead of parsing

### Example prompts or workflows

### Additional context

_No response_