Identify: EXTERNAL DATA view type #12596

[rowheat02]

Description

This PR introduces a new Identify view type called External Data. It allows identified features to be linked to a separate WFS-enabled table through a configurable CQL filter and displays selected attributes from the related records.

Screen.Recording.2026-08-05.at.15.14.53.mov

Also, added configurable attributes to Properties views (from issue) , custom media rending will be handled in #12597

Please check if the PR fulfills these requirements

• The commit message follows our guidelines: https://github.com/geosolutions-it/MapStore2/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x", remove the others)

• Feature

Issue

What is the current behavior?

#12596
#12598

What is the new behavior?

A new External Data Identify view is available. It allows users to configure an external WFS layer and build a CQL filter using properties from the identified feature.
Also, for Properties views, users can configure which field to hide and change the alias of some fields.

Breaking change

Does this PR introduce a breaking change? (check one with "x", remove the other)

• Yes, and I documented them in migration notes
• No

Other useful information

• External Data currently supports WFS sources only.
• CQL templates can reference identified feature properties using ${properties.name} or ${properties['name']}.
• One external request is executed per identified feature, with results limited to 10 features per request.
• Requests use the existing MapStore Axios and proxy handling.