Configure sections were local useState, so they could not be linked or bookmarked and always opened on the default section. Each section is now a route (/configure, /configure/models, /configure/workspace-prompt, /configure/proactivity, /configure/automations), mirroring the existing /integrations/[card] pattern. The shell renders from the segment layout so switching sections does not remount the app, and legacy /?view=configure links forward to /configure.
Fixes ENG-1140
