[Fix] Home sandbox dropdown shows unconfigured providers

[roomote-roomote]

Opened on behalf of Matt Rubens. Follow up by mentioning @openmote, in the web UI, or in Slack.

Related issue

N/A — internal Roomote product fix from Slack.

Why this PR exists

• A maintainer explicitly invited this PR in the linked issue or discussion
• I am a maintainer / this is internal Roomote work

What changed

The home Sandbox provider dropdown no longer lists unconfigured providers. The home page loads configured sandboxes server-side and only offers those options.

Follow-up: when the saved default is missing from that list, the pre-selected provider now follows the same setup-catalog display order as the dropdown (instead of the raw compute-provider IDs order).

How it was tested

• Unit tests for configured-provider listing, including catalog display order
• Home unit tests for filtered providers and catalog-ordered fallback selection
• pnpm lint and pnpm check-types

Screenshots

Checklist

• The PR title follows the repo convention: [Fix], [Feat], [Improve], [Refactor], [Docs], or [Chore] followed by a user-facing description
• This PR is small and scoped to one change
• pnpm lint and pnpm check-types pass locally
• I added tests or included a clear manual validation note above
• I removed secrets, tokens, private keys, and customer data from code, logs, and screenshots
• If this change should appear in the changelog, I ran pnpm changeset

[roomote-roomote]

Re-reviewed the latest change. No new code issues found — the SETUP_COMPUTE_PROVIDER_CATALOG-ordered listing and Home filtering keep the fallback aligned with the first visible dropdown row, and the delta tests pass. See task

• Low — Home fallback vs dropdown order: fixed by returning configured providers in SETUP_COMPUTE_PROVIDER_CATALOG order and filtering available options through that same order on Home.