fix: alphabetize imports, bracket IPv6 hostnames, clarify SQL host

- Move env import to correct alphabetical position
- Wrap IPv6 literal hostnames in brackets for valid URL construction
- Add comment explaining why connectionStringHost is separate from
  NITRIC_HOSTNAME

Author: tom-groves

pkg/cloud/cloud.go

@@ -19,6 +19,7 @@ package cloud
 import (
 	"fmt"
 	"io"
+	"strings"
 	"sync"
 
 	"google.golang.org/grpc"
@@ -35,10 +36,10 @@ import (
 	"github.com/nitrictech/cli/pkg/cloud/secrets"
 	"github.com/nitrictech/cli/pkg/cloud/sql"
 	"github.com/nitrictech/cli/pkg/cloud/storage"
+	"github.com/nitrictech/cli/pkg/cloud/env"
 	"github.com/nitrictech/cli/pkg/cloud/topics"
 	"github.com/nitrictech/cli/pkg/cloud/websites"
 	"github.com/nitrictech/cli/pkg/cloud/websockets"
-	"github.com/nitrictech/cli/pkg/cloud/env"
 	"github.com/nitrictech/cli/pkg/grpcx"
 	"github.com/nitrictech/cli/pkg/netx"
 	"github.com/nitrictech/cli/pkg/project/dockerhost"
@@ -258,6 +259,11 @@ type LocalCloudOptions struct {
 func New(projectName string, opts LocalCloudOptions) (*LocalCloud, error) {
 	hostname := env.NITRIC_HOSTNAME.String()
 
+	// Bracket IPv6 literals for use in URLs (RFC 3986)
+	if strings.Contains(hostname, ":") && !strings.HasPrefix(hostname, "[") {
+		hostname = "[" + hostname + "]"
+	}
+
 	localTopics, err := topics.NewLocalTopicsService()
 	if err != nil {
 		return nil, err
@@ -314,6 +320,9 @@ func New(projectName string, opts LocalCloudOptions) (*LocalCloud, error) {
 		return nil, err
 	}
 
+	// connectionStringHost controls how application services reach the Postgres container,
+	// which is distinct from NITRIC_HOSTNAME (how callers reach the Nitric backend).
+	// Postgres is its own container with host-mapped ports, so it needs separate addressing.
 	connectionStringHost := "localhost"
 
 	// Use the host.docker.internal address for connection strings with local cloud run mode