Geo Sites - Rename geo_nodes Vuex store

What does this MR do and why?

This change is MR 1 of 5 for #393925 (closed)
Split off from !113598 (closed)

Geo has rebranded the term Nodes => Sites. We have taken the Facade-first approach to rename only customer facing content while leaving all the technical content like file names, method names, variable names.

Now that the rebrand is mature and we are sure the term Sites is here to stay we are aiming to complete the rename for the technical side of things too.

Focus of this MR

This MR is focused on renaming the Vuex store inside of the geo_nodes scope. This includes all actions, getters, and state. Naturally renaming these requires them to be also renamed in the components that use them.

In the following MR: !113771 (merged) we plan to complete the rename of this scope by changing the file names and all component internals.

Screenshots or screen recordings

No change or console errors

Find in files results

geo_nodes/store	spec/geo_nodes/store

notes about find results:

1. in geo_nodes/store the only result has comment explaining why (related to API)
2. in ee/geo_nodes/store
   • Many results are due to file location geo_nodes/* which is addressed in !113771 (merged)
   • All other results have comments explaining why (all related to API)

How to set up and validate locally

1. Fetch and checkout this branch
2. Setup Geo (How to setup Geo)
3. Access your Primary GDK UI
4. Navigate to Geo Dashboard (/admin/geo/sites)
5. Ensure everything looks as it has and no console errors

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.