fix: Caddy config regeneration due to non-deterministic container serialisation (fixes #111)

internal/machine/caddyconfig/caddyfile.go

@@ -19,7 +19,7 @@ import (
 )
 
 const (
-	caddyfileHeaderFmt = `# Caddyfile autogenerated by Uncloud (DO NOT EDIT): %s
+	caddyfileHeaderFmt = `# Caddyfile autogenerated by Uncloud on machine '%s' (DO NOT EDIT): %s
 # Automatically updated on service or health status changes.
 # Docs: https://uncloud.run/docs/concepts/ingress/overview
 `
@@ -68,8 +68,10 @@ https://{{$hostname}} {
 type CaddyfileGenerator struct {
 	// machineID is the unique identifier of the machine where the controller is running.
 	machineID string
-	validator CaddyfileValidator
-	log       *slog.Logger
+	// machineName is the human-friendly name of the machine.
+	machineName string
+	validator   CaddyfileValidator
+	log         *slog.Logger
 }
 
 // CaddyfileValidator is an interface for validating Caddyfile configurations.
@@ -77,14 +79,17 @@ type CaddyfileValidator interface {
 	Validate(ctx context.Context, caddyfile string) error
 }
 
-func NewCaddyfileGenerator(machineID string, validator CaddyfileValidator, log *slog.Logger) *CaddyfileGenerator {
+func NewCaddyfileGenerator(
+	machineID, machineName string, validator CaddyfileValidator, log *slog.Logger,
+) *CaddyfileGenerator {
 	if log == nil {
 		log = slog.Default()
 	}
 	return &CaddyfileGenerator{
-		machineID: machineID,
-		validator: validator,
-		log:       log,
+		machineID:   machineID,
+		machineName: machineName,
+		validator:   validator,
+		log:         log,
 	}
 }
 
@@ -124,7 +129,7 @@ func (g *CaddyfileGenerator) Generate(
 		return "", fmt.Errorf("generate base Caddyfile from service ports: %w", err)
 	}
 
-	caddyfileHeader := fmt.Sprintf(caddyfileHeaderFmt, time.Now().UTC().Format(time.RFC3339))
+	caddyfileHeader := fmt.Sprintf(caddyfileHeaderFmt, g.machineName, time.Now().UTC().Format(time.RFC3339))
 	if !includeCustom {
 		return fmt.Sprintf("%s\n%s\n%s", caddyfileHeader, caddyfile, caddyfileUnavailabeFooter), nil
 	}