Remove outdated display structured history view

[guerler]

This PR removes the display structured view component, controller endpoint and route. Having talked to several contributors, we recognized that this feature has little utility and does not work for larger histories. It also utilized and outdated mix between backend produced html strings and a client-side patching mechanism. Additionally this PR removes the beta toggle switch, which used to allow switching between the legacy and the current history. This is a step towards finally removing the legacy history from the code base.

How to test the changes?

(Select all options that apply)

• I've included appropriate automated tests.
• This is a refactoring of components with existing test coverage.
• Instructions for manual testing are as follows:
  1. [add testing steps and prerequisites here if you didn't write automated tests covering all your changes]

License

• I agree to license these and all my past contributions to the core galaxy codebase under the MIT license.