feat: add tenant and user management with migrations, handlers, and tests

- Implemented tenant and user management features including:
  - Tenant creation and management with associated migrations.
  - User creation and management with associated migrations.
  - Tenant membership management with associated migrations.
  - Platform user roles management with associated migrations.
  - Quota management with associated migrations.
  - Article and template management with associated migrations.
- Added HTTP handlers for templates and workspaces.
- Created tests for protected and public routes.
- Introduced a script to check tenant scope in SQL queries.
- Documented task plan for backend completion and frontend foundation.

server/internal/tenant/domain/generation_task.go

@@ -0,0 +1,19 @@
+package domain
+
+import "time"
+
+type GenerationTask struct {
+	ID                 int64
+	TenantID           int64
+	ArticleID          *int64
+	TaskBatchID        *string
+	QuotaReservationID *int64
+	TaskType           string
+	RequestHash        *string
+	InputParamsJSON    map[string]interface{}
+	Status             string
+	ErrorMessage       *string
+	StartedAt          *time.Time
+	CompletedAt        *time.Time
+	CreatedAt          time.Time
+}