feat(services): traefik routing overrides via allowlisted middleware labels (#64)

services.traefik_labels (jsonb) holds operator-defined Traefik
middlewares keyed 'middlewares.<name>.<type>[.<field>]', validated
against an allowlist at write time. edgeLabels (extracted from
createReplica) scopes each definition to the service router as
<router>-<name> and auto-attaches it to the router's middleware chain
after builtins. Router/service/provider-level keys are rejected.

Surfaces: create/update API fields, services create/update
--traefik-label (repeatable, key=value), MCP arg docs, OpenAPI +
regenerated types, service-page Access editor (Routing overrides
card + textarea).

Also marks three stale ROADMAP2 items shipped: notification producers
round-out, build-on-node (PR #60), mobile env/domains/scaling (PR #61).

Generated with [Devin](https://devin.ai)

Co-authored-by: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

app/backend/internal/api/runtime.go

@@ -121,6 +121,7 @@ func serviceRuntimeSpec(db *database.DB, service Service) (deployment.RuntimeSpe
 	spec.Volumes = loadServiceVolumes(db, service.ID)
 	spec.Domains = serviceDomainNames(db, service.ID, service.Domain)
 	spec.Maintenance, spec.BasicAuthUsers = serviceAccess(db, service.ID)
+	spec.TraefikLabels = serviceTraefikLabels(db, service.ID)
 	if spec.Maintenance {
 		spec.MaintenanceURL = maintenanceURL(db)
 	}