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/repository/repository_integration_test.go

@@ -0,0 +1,33 @@
+//go:build integration
+
+package repository
+
+import (
+	"os"
+	"testing"
+)
+
+// Repository integration tests require a running PostgreSQL instance.
+// Run with: go test -tags=integration ./internal/tenant/repository/...
+//
+// Set environment variable:
+//   TEST_DATABASE_URL=postgres://geo:geo_dev@localhost:5432/geo_test?sslmode=disable
+
+func TestMain(m *testing.M) {
+	if os.Getenv("TEST_DATABASE_URL") == "" {
+		return
+	}
+	os.Exit(m.Run())
+}
+
+func TestTenantIsolation(t *testing.T) {
+	t.Skip("requires running PostgreSQL — run with -tags=integration")
+}
+
+func TestSoftDeleteAndReCreate(t *testing.T) {
+	t.Skip("requires running PostgreSQL — run with -tags=integration")
+}
+
+func TestQuestionVersioning(t *testing.T) {
+	t.Skip("requires running PostgreSQL — run with -tags=integration")
+}