refactor: framework modules log through diary components

- Each module logs through diary.For(<package>): cabana, lagoon, attach, cooler, postcard, beachcomber, lighthouse, centrifugo, flare, phrasebook, wristband, bouncer
- App-published *slog.Logger overrides stay first; messages and attributes unchanged
- sunscreen: InstallDefault documented as the compatibility entry point; diary wraps every channel
- READMEs list diary as a dependency; logging docs: plugins use diary.For

modules/lighthouse/lighthouse.go

@@ -18,10 +18,15 @@ import (
 
 	"git.golem15.com/golem15/summercms/modules/backpack"
 	"git.golem15.com/golem15/summercms/modules/compass"
+	"git.golem15.com/golem15/summercms/modules/diary"
 	"git.golem15.com/golem15/summercms/modules/lagoon"
 	"gorm.io/gorm"
 )
 
+// moduleLog is lighthouse's logger: records carry component=lighthouse and follow
+// log.components.lighthouse (diary).
+var moduleLog = diary.For("lighthouse")
+
 const (
 	// DefaultDriver is the driver used when realtime.driver is empty.
 	DefaultDriver = "null"
@@ -141,10 +146,11 @@ func (s *Service) Registry() *Registry {
 	return s.registry
 }
 
-// Logger returns the app logger the service and its driver log through.
+// Logger returns the app logger the service and its driver log through: the
+// logger the application published, else the lighthouse component logger.
 func (s *Service) Logger() *slog.Logger {
 	if s == nil || s.log == nil {
-		return slog.Default()
+		return moduleLog
 	}
 	return s.log
 }
@@ -198,5 +204,5 @@ func loggerFromApp(app *backpack.App) *slog.Logger {
 			return log
 		}
 	}
-	return slog.Default()
+	return moduleLog
 }