Review of the org-scoping pass found that org_id on a query filter
protects the row you look up, but does nothing when a handler accepts a
foreign resource ID as data and a downstream unscoped query consumes it.
- AssignKey: verify key and server both belong to the org
- BuildAuthorizedKeys: resolve server first, scope assignments and keys
to that server's org (was honouring foreign assignment rows)
- Workflows: validate TargetServerIDs on create/update and re-check at
trigger time
- Monitor incidents/uptime handlers: gate on org-scoped GetMonitor
- GetChannels: take orgID; validate channel_ids on monitor create/update
- Secret and default-step unique indexes: scope to org_id so a second
org no longer hits E11000
- DeleteServer/DeleteMonitor: scope cascading deletes