Pipeline Graph Structural Update: Add New Links Component

What does this MR do?

This latest addition to the #276949 (closed) saga adds the a link component and applies it to the Big Pipeline Graph.

There are still a few bugs, which will be dealt with in a followup (see: #297394 (closed)). It is behind the :graphql-pipeline-details feature flag, which is off by default.

Screenshots (strongly suggested)

See it on your screen

To see locally, turn on the :graphql-pipeline-details flag and navigate to any pipeline.

Does this MR meet the acceptance criteria?

Conformity

• Code review guidelines
• Merge request performance guidelines
• Style guides

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 #276949 (closed)