[federation][resolvers] Add `generateInternalResolversIfNeeded. __resolveReference` to generate `__resolveReference` only when resolvable

[eddeee888]

Description

From Apollo Federation doc: https://www.apollographql.com/docs/federation/federated-types/federated-directives/#resolvable: when there's no resolvable @keys on an object type in a subgraph, we cannot move to the object type in said subgraph.

This PR:

• adds generateInternalResolversIfNeeded.__resolveType
• By default, generateInternalResolversIfNeeded.__resolveType = false generates optional __resolveType without checking whether there's at least one resolvable @key
• When generateInternalResolversIfNeeded.__resolveType = true:
  • avoids generating __resolveReference if there's no resolvable @key
  • generates non-required __resolveReference for resolvable @key and skip non-resolvable ones
  • report whether a type has reference resolver in meta so something like Server Preset can handle it correctly

Type of change

Please delete options that are not relevant.

• [x] New feature (non-breaking change which adds functionality)

Screenshots/Sandbox (if appropriate/relevant):

Adding links to sandbox or providing screenshots can help us understand more about this PR and take action on it as appropriate

How Has This Been Tested?

• [x] Unit tests for federation and resolvers plugin

[changeset-bot[bot]]

🦋 Changeset detected

Latest commit: 479c1af93bb14f5e9a4626e50a1a6057c0e1af8d

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 10 packages

| Name | Type | | ------------------------------------------ | ----- | | @graphql-codegen/visitor-plugin-common | Minor | | @graphql-codegen/typescript-resolvers | Minor | | @graphql-codegen/plugin-helpers | Minor | | @graphql-codegen/typescript-document-nodes | Patch | | @graphql-codegen/gql-tag-operations | Patch | | @graphql-codegen/typescript-operations | Patch | | @graphql-codegen/typed-document-node | Patch | | @graphql-codegen/typescript | Patch | | @graphql-codegen/graphql-modules-preset | Patch | | @graphql-codegen/client-preset | Patch |

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[github-actions[bot]]

🚀 Snapshot Release (alpha)

The latest changes of this PR are available as alpha on npm (based on the declared changesets):	Package	Version	Info
@graphql-codegen/cli	5.0.3-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/visitor-plugin-common	5.4.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/typescript-document-nodes	4.0.10-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/gql-tag-operations	4.0.10-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/typescript-operations	4.3.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/typescript-resolvers	4.3.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/typed-document-node	5.0.10-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/typescript	4.1.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/client-preset	4.4.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/graphql-modules-preset	4.0.10-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/testing	3.0.4-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎
@graphql-codegen/plugin-helpers	5.1.0-alpha-20240930134227-479c1af93bb14f5e9a4626e50a1a6057c0e1af8d	npm ↗︎ unpkg ↗︎

[github-actions[bot]]

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