Write a SpacetimeDB backend module in Rust that defines one table and seeds two rows.

TABLE
- account
  - Struct: Account
  - Columns:
    - id: u64 (primary key, auto_inc)
    - email: String (unique)
    - name: String
  - Indexes:
    - by_name: btree(name)

REDUCERS
- seed: insert exactly these rows into account (IDs are auto-assigned)
  - (email="a@example.com", name="Alice")
  - (email="b@example.com", name="Bob")
