Add workspace sharing via gist or link

[patmakesapps]

Problem

There is no way to share the current conversation and codebase state with others for debugging help or showing off work.

Proposed Solution

• Export conversation + relevant code
• Upload to gist, pastebin, or custom service
• Could integrate with lumalien.com
• Privacy controls: include/exclude files

Acceptance Criteria

• Can export conversation and code to a shareable format
• Upload to at least one sharing service (e.g. GitHub Gist)
• Privacy controls to include/exclude files
• Shareable link is generated