What this PR does / why we need it:

Currently, all fields regardless of type are indexed in Solr as English text (text_en). With this PR, numerical and date fields are indexed in Solr with appropriate types:

I chose to index dates as DateRangeField because they can be used to represent dates to any precision, e.g. a day YYYY-MM-DD, a month YYYY-MM or a year YYYY. See: Date Formatting and Date Math :: Apache Solr Reference Guide

This matches the allowed formats in a date field as defined by Dataverse.

This means that range queries are now possible on numerical and date fields, e.g. exampleIntegerField:[25 TO 50] or exampleDateField:[2000-11-01 TO 2014-12-01].

Which issue(s) this PR closes:

This PR implements ranged queries as discussed in #370 (issue was already closed)

This issue is related to #8813 and IQSS/dataverse-frontend#278 (the range queries that are now possible lay the groundwork for a nicer search facet UI)

Special notes for your reviewer:

For testing, I've created a sample TSV containing all relevant fields here.

Suggestions on how to test this:

1. Load sample TSV and update + reload Solr schema as described in docs
2. In the UI:
   1. Activate metadata block
   2. Activate facets for all three fields
   3. Create dataset with values in all three fields
3. Run test range queries via the search bar, e.g. exampleIntegerField:[25 TO 50] or exampleDateField:[2000-11-01 TO 2014-12-01]
4. Check that facets are working correctly

Does this PR introduce a user interface change? If mockups are available, please link/include them here:

Facets still look the same as before. There is only a small change in the highlighting of search results, see my comment below

Is there a release notes update needed for this change?:

Yes, there should be an info text describing the new feature + instructions for how to activate the feature:

• the Solr schema.xml needs to be updated
• all datasets need to be reindexed

Additional documentation:

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