Download collections from UI

[brandonjackson]

Context

Collections are a shared data layer across workflows, but users currently have no way to inspect their contents from the UI. The admin page (Project Settings → Collections) only supports create, edit, and delete — to see what's actually inside a collection, users resort to writing throwaway workflows with collections.get() or using the CLI. Items are often 1MB+, so logging to state isn't practical.

Acceptance Criteria

• Each collection row displays a Download button alongside Edit and Delete, using the existing button style
• Clicking Download exports the collection contents as a .json file named {collection-name}.json
• Collections over 50 MB (up for discussion): Download button is disabled with a tooltip — "Too large to download. Use the CLI instead."

Open Questions

• Is 50 MB the right threshold, or should we go lower to keep browser performance safe?
• Permissions? Scope to project admins only, or available to all project members?

[brandonjackson]

I started this with Claude Code here - not sure if it's any good! Feel free to bin/restart