Graph Needs View: Toggle With Dropdown

What does this MR do?

This MR is an interstitial MR for #298930 (closed). The code in this is behind the pipeline_graph_layers_view and graphql_pipeline_details flags. This step follows !56865 (merged).

In the stages view, which is the default, no links should show between jobs. In the needs view, links should show. Changing options in the dropdown should change the view type. The view type changes in main and linked (upstream/downstream) pipelines.

You may wonder why if the stage version doesn't show links, the LinksInner component is written so as to show them for both graph types and recalculate when switching. The answer to that is the Links will also be used in the Pipeline Editor vis, and there the rules will be different. It's also possible the rules will change here.

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

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Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Related to #298930 (closed)