[Feature] Live mode and extension: support screenshots instead of selecting elements (e.g. for flutter web apps)

[orakemu]

What problem does this solve?

Right now the chrome extension and the live mode do not work for flutter based web apps.

Proposed solution

Allow users to manually select/screenshot part of the ui and add comments.

Provider(s) this applies to

• Cursor
• Claude Code
• Gemini CLI
• Codex CLI
• VS Code Copilot
• Kiro
• OpenCode
• All providers

Alternatives considered

Since flutter renders the whole app in a html canvas, I guess screenshots are the only solution.