Restrict V5 application and resource-connection creation to team admins.
Resolve project, environment, and application from query params and keep
session selection in sync. Surface V5 apps on the v4 resource index and
count them for project/environment emptiness. Create the flux data dir
on install and upgrade.
Split V5 dashboard behavior into domain controllers and policies,
add agent token rotation/revocation, status reconciliation jobs,
ingress firewall syncing, and canvas connection APIs.
Add migrations for V5 status tracking, server capabilities, resource
connection aliases, and revoked agent tokens.
