Can not derive model properties

[dvv]

Describe the bug

Hello!

I'm struggling with the following piece of tsp:

model Object {
  @visibility(Lifecycle.Read)
  @key id: string,
}

model Item extends Object {
  name: string,
  // other props...
}

@doc("An excerpt of Item for Account")
model Account_Item is PickProperties<Item, "id" | "name">;

model Account extends Object {

  @visibility(Lifecycle.Read)
  item: Account_Item,
  // item: PickProperties<Item, "id" | "name">,

  @visibility(Lifecycle.Create, Lifecycle.Update)
  // item_id: Account_Item.id, // <------------ ERR: Model doesn't have member id
  item_id: Item.id,                   // <------------ ERR: Duplicate type name: 'Account'

}

// below should go definitions using Create<Account>, Update<Account> hence lifecycles.

Both kinds of definition of item_id seem to be evident to me, but they result in throwing errors (see comments).
Both errors seem a bit inadequate to me, esp. "Duplicate type name: 'Account'".

Am I doing something fundamentally wrong?
How else to express a model property that is an id of another model and must be visible at create/update lifecycle only?

TIA

Reproduction

model Object {
  @visibility(Lifecycle.Read)
  @key id: string,
}

model Item extends Object {
  name: string,
  // other props...
}

@doc("An excerpt of Item for Account")
model Account_Item is PickProperties<Item, "id" | "name">;

model Account extends Object {

  @visibility(Lifecycle.Read)
  item: Account_Item,
  // item: PickProperties<Item, "id" | "name">,

  @visibility(Lifecycle.Create, Lifecycle.Update)
  // item_id: Account_Item.id, // <------------ ERR: Model doesn't have member id
  item_id: Item.id,                   // <------------ ERR: Duplicate type name: 'Account'

}

// below should go definitions using Create<Account>, Update<Account> hence lifecycles.

Checklist

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• Check that this is a concrete bug. For Q&A open a GitHub Discussion.
• The provided reproduction is a minimal reproducible example of the bug.

[timotheeguerin]

There is 2 issues here:

1. Cannot reference id, this is currently due to a limitation on how TypeSpec does member resolution and cannot reference anything that cannot be staticaly linked(need to involve a template instantation to know) Reference property spread in template #7673
2. Does seem like a bug, repros with just that

model Object {}

model Account extends Object {
  @visibility(Lifecycle.Create, Lifecycle.Update)
  item_id: string;
}

Playground

[dvv]

@timotheeguerin thank you for the explanation!

Please comment on the following:

model Foo {
  @visibility(Lifecycle.Read) bar: string,
  @visibility(Lifecycle.Create) bar: string, // ERR: Model already has a property named bar
  @visibility(Lifecycle.Update) bar: string, // ERR: Model already has a property named bar
}

I expected the set of properties not to clash due to orthogonal visibilities.