Explore Tab will crash if too many sites are selected

[cristinamullin]

Describe the bug

The application will crash on the Explore tab if too many sites are selected for mapping.

To Reproduce

Steps to reproduce the behavior:

1. Run query with the following WQP filter inputs:

• countrycode: Atlantic Ocean and Pacific Ocean
• sampleMedia: "Water" "water"
• providers: "NWIS" "STORET"

2. Run Tests on flag tab

3. Skip ahead to explore tab

4. Generate Groups with TADA.ComparableDataIdentifier entered as the grouping column

7. Generate Map for "PLASTICS #/100ML

This is when the app crashes and you get the error below:

Error: (converted from warning) Error in : (converted from warning) Error in : (converted from warning) The select input "figures_1-selsites1" contains a large number of options; consider using server-side selectize for massively improved performance. See the Details section of the ?selectizeInput help topic.

Expected behavior

The app should not crash.

If you enter ?selectizeInput to the console. There are instructions here on how to change this to a server side selectize input instead: https://shiny.posit.co/r/articles/build/selectize/

This pertains to what we currently have in line 532 of mod_figures.R
shiny::selectizeInput(ns("selsites1"), "Select sites", choices = sites, selected = sites[1], multiple = TRUE, width = "100%")