Write a SpacetimeDB backend module in TypeScript that defines one table and a reducer performing CRUD operations.

TABLE
- user
  - Fields:
    - id: number (i32, primary key)
    - name: string
    - age: number (i32)
    - active: boolean

REDUCERS
- crud: no arguments, performs the following operations in order:
  1. Insert (id=1, name="Alice", age=30, active=true)
  2. Insert (id=2, name="Bob", age=22, active=false)
  3. Update row with id=1 to (id=1, name="Alice2", age=31, active=false)
  4. Delete row with id=2
