feat(studio): complete agent catalog and detail workflow

[evanlowe]

Summary

• add a responsive, server-paginated Agent catalog as the default authenticated landing page
• connect create, deploy, use, switch, and focused detail flows while keeping detail viewing separate from Agent selection
• show connection progress, connected state, and a disconnected guidance banner
• keep deployment progress inside the focused detail page and remove it after a successful release
• expose authorized Runtime deletion, detailed deployment configuration, capability badges, and refreshed execution topology
• support the existing temporary-session launch flow and mark unavailable Agent families as coming soon
• recover stale lazy-loaded assets automatically instead of leaving a blank page after a release

Validation

• completed the create, deploy, detail, use, switch, pagination, and custom-create flows against the local Studio preview
• verified account-backed empty states, loading overlays, connection transitions, deployment progress, deletion permissions, and execution-flow refresh
• npm test (256 passed)
• npm run build
• git diff --check for hand-written source and tests
• uv run pytest -n 16 (942 passed, 2 skipped)