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/shared/repository/postgres/postgres.go

@@ -0,0 +1,32 @@
+package postgres
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/jackc/pgx/v5/pgxpool"
+
+	"github.com/geo-platform/tenant-api/internal/shared/config"
+)
+
+func NewPool(ctx context.Context, cfg config.DatabaseConfig) (*pgxpool.Pool, error) {
+	poolCfg, err := pgxpool.ParseConfig(cfg.DSN())
+	if err != nil {
+		return nil, fmt.Errorf("parse pool config: %w", err)
+	}
+
+	poolCfg.MaxConns = int32(cfg.MaxOpenConns)
+	poolCfg.MinConns = int32(cfg.MaxIdleConns)
+
+	pool, err := pgxpool.NewWithConfig(ctx, poolCfg)
+	if err != nil {
+		return nil, fmt.Errorf("create pool: %w", err)
+	}
+
+	if err := pool.Ping(ctx); err != nil {
+		pool.Close()
+		return nil, fmt.Errorf("ping postgres: %w", err)
+	}
+
+	return pool, nil
+}