fix: nodes field returning nil on nested collections

[nicolerenee]

The upstream PR ent/contrib#602 appears to have missed adding the check for the nodes field being used in the collections template. This is used when you call a collection from another collection, for example:

query {
  loadBalancer(id: "lb-123"){
    ports {
      nodes {
        pools {
          nodes {
            id
          }
        }
      }
    }
  }
}

Before this fix the pools.nodes would come back as an empty list, with this fix it's properly filled out.

[Copilot]

Pull Request Overview

This PR fixes an issue where the nodes field was returning nil on nested collections in GraphQL queries. The fix adds support for the nodes field check in the collection template, ensuring that nested collection queries properly populate the nodes field instead of returning empty lists.

• Adds a new collection template with the necessary nodes field support
• Registers the collection template in the generator's WithConnectionNodes extension
• Includes the missing check for hasCollectedField(ctx, append(path, nodesField)...) in the template logic

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
entx/template/collection.tmpl	New template file that adds nodes field support to collections with the critical fix on line 94
entx/template.go	Adds CollectionTemplate variable to register the new template
entx/generator.go	Updates WithConnectionNodes to include the CollectionTemplate alongside PaginationTemplate

[andy-v-h]

Good to see some activity here :)