[FEATURE] Add option to suppress tool call UI during agent/skill execution

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

## Why it matters

• Custom skill authors design formatted console output (headers, tables, blockquotes) that gets buried between tool call blocks
• End users running skills care about results, not implementation details
• Transparency is still preserved in the conversation history — just not foregrounded in the UI

Proposed Solution

A setting or flag to minimize/hide tool call chrome during execution. Examples:

• --quiet or --minimal-ui CLI flag
• A displayToolCalls: false setting in settings.json
• A per-skill frontmatter option like ui: minimal

The agent's text output would still display normally — only the tool invocation blocks would be collapsed or hidden.

When running custom agents/skills (slash commands), the console displays every intermediate tool call (Bash, Read, Edit, Grep, etc.) as collapsible UI blocks. For agents that produce clean formatted output, this adds visual noise — the user wants to see the agent's results, not every file read or bash command along the way.

Alternative Solutions

_No response_

Priority

Critical - Blocking my work

Feature Category

CLI commands and flags

Use Case Example

_No response_

Additional Context

_No response_