refactor(db): port deployments to sqlc (#78)

Tranche 4: all 32 raw sites in deployments.go — paginated service list,
the accessible-feed joins (owner/member/admin/approved), service+owner
load, deployment insert, status transitions (fail/complete/set), the
10-field progress sync, cancel access check, rollback reads/inserts, and
the published_port reuse read. The shared serviceForDeployFromRow mapper
now feeds both the preview and deployments loaders. Live test covers the
full lifecycle: insert, list, access join, feed predicate, queued →
deployed sync, failed transition.

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

app/backend/internal/api/preview_environments.go

@@ -775,11 +775,7 @@ func resolvePreviewHost(db *database.DB, cloneID uuid.UUID, envName string) stri
 
 // loadServiceForDeploy hydrates the Service fields runDeploymentAndSync
 // needs — mirrors the loader in handleDeployService.
-func loadServiceForDeploy(db *database.DB, serviceID uuid.UUID) (Service, error) {
-	r, err := sqlcdb.New(db.DB).GetServiceForDeploy(context.Background(), serviceID)
-	if err != nil {
-		return Service{}, err
-	}
+func serviceForDeployFromRow(r sqlcdb.GetServiceForDeployRow) Service {
 	return Service{
 		ID: r.ID, ProjectID: r.ProjectID, Name: r.Name, Type: r.Type.String,
 		Status: r.Status.String, Image: r.Image.String, Command: r.Command.String,
@@ -791,7 +787,15 @@ func loadServiceForDeploy(db *database.DB, serviceID uuid.UUID) (Service, error)
 		Builder: r.Builder, CPUReserve: r.CpuReserve, MemoryReserve: r.MemoryReserve,
 		StaticBuildCmd: r.StaticBuildCmd, StaticDir: r.StaticDir,
 		CreatedAt: r.CreatedAt.Time, UpdatedAt: r.UpdatedAt.Time,
-	}, nil
+	}
+}
+
+func loadServiceForDeploy(db *database.DB, serviceID uuid.UUID) (Service, error) {
+	r, err := sqlcdb.New(db.DB).GetServiceForDeploy(context.Background(), serviceID)
+	if err != nil {
+		return Service{}, err
+	}
+	return serviceForDeployFromRow(r), nil
 }
 
 // StartPreviewSweeper expires preview environments past their TTL — tears