PrimaryColumns other than 'id' are not supported in codegen

[jeffrey-computers]

Describe the bug
TypeORM @PrimaryColumn supports fields with an arbitrary name, but Squid's codegen only supports a PrimaryColumn named 'id'. If an 'id' value is not included in the schema, then it is added automatically.

This means code comments are required to explain what the entity's id value is, rather than semantic field names. As is evidenced in your own example project!

To Reproduce
Create a schema.graphql file like:

type TestEntity @entity {
  someUniqueIdentifier: ID!
  foo: boolean;
}

Codegen automatically creates a @PrimaryColumn_() of id. The intended primary column is someUniqueIdentifier

Expected behavior

• Schema entity fields typed as ID! should be used for TypeORM's PrimaryColumn instead of id.
• No id field should be created unless an ID! is missing.

i.e. the above example
Should yield:

@Entity_()
export class TestEntity {
    constructor(props?: Partial<TestEntity>) {
        Object.assign(this, props)
    }

    @PrimaryColumn_()
    someUniqueIdentifier!: string

    @Column_("bool", {nullable: true})
    foo!: boolean | undefined | null
}