iOS debugger agent

Use the XcodeBuildMCP tools (https://github.com/getsentry/XcodeBuildMCP). Without it, fall back to xcrun simctl and xcodebuild, noting that tapping and typing then need a UI test.

• Use a booted simulator. Ask before booting one.
• Set session defaults (project or workspace, scheme, simulator id) before building.
• After a build, confirm the app launched with a UI description or screenshot before interacting.
• Describe the UI before tapping. Prefer id or label over coordinates.