Update MinIO bucket configuration and enhance dashboard service caching

- Changed the default MinIO bucket name from "opplens-documents" to "opplens" across multiple configuration files.
- Introduced caching for dashboard statistics in the service layer to improve performance and reduce redundant data fetching.
- Implemented a mutex for thread-safe access to cached statistics, ensuring data integrity during concurrent requests.

This update streamlines the configuration for the AI summarizer and optimizes the dashboard service, enhancing overall system efficiency.

cmd/worker/bootstrap/config.go

@@ -48,5 +48,5 @@ type AISummarizerConfig struct {
 	MinioSecretKey        string        `env:"AI_SUMMARIZER_MINIO_SECRET_KEY" envDefault:""`
 	MinioUseSSL           bool          `env:"AI_SUMMARIZER_MINIO_USE_SSL" envDefault:"false"`
 	MinioRegion           string        `env:"AI_SUMMARIZER_MINIO_REGION" envDefault:"us-east-1"`
-	MinioBucket           string        `env:"AI_SUMMARIZER_MINIO_BUCKET" envDefault:"opplens-documents"`
+	MinioBucket           string        `env:"AI_SUMMARIZER_MINIO_BUCKET" envDefault:"opplens"`
 }