Add /browser or /playwright to enable browser automation, matching /computer #5152

Describe the feature or problem you'd like to solve

Computer Use is easy to discover and enable with /computer, but there is no equivalent browser-automation command in my Copilot CLI installation (Windows, version 1.0.99-0). After enabling Computer Use, /mcp lists only computer-use and github-mcp-server, and copilot mcp get playwright reports Server "playwright" not found. Users should have a similarly simple, first-party path to enable browser automation without manually configuring an MCP server or separately researching tools.

Proposed solution

Related: #2801 asks for VS Code browser integration; this request is for standalone CLI enable/disable/status UX. The documentation inconsistency is tracked separately in github/docs#43371.

Example workflows: verify a local web app, reproduce a UI bug and capture a screenshot, and check desktop/mobile layouts.

Add a first-party /browser command (or /playwright) with an experience comparable to /computer:

• Show browser automation status and provide enable/disable controls.
• Set up the supported browser automation integration without requiring users to hand-edit MCP configuration.
• Explain and request consent before installing any required dependencies or browsers.
• Make the enabled integration and connection status visible in /mcp when MCP-backed, or clearly show its status if implemented another way.
• Respect existing tool permissions and clearly explain browser session isolation and access to signed-in sessions.

The implementation could use Playwright MCP, playwright-cli, or another supported backend; the core request is a discoverable one-command experience, not a specific backend or a dependency on VS Code. This would make web-app testing and browser tasks as approachable as desktop Computer Use.

Example prompts or workflows

No response

Additional context

No response