Add Viz Guidance to ChatGXY

[guerler]

xref: #21609. Explores an early visualization guidance addition for ChatGXY, focused on clarifying visualization related intent and language at the UI level. This is an initial, lightweight attempt intended as a concrete starting point for iteration.

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.