Enhancement picking of imagery feature

[3DGISKing]

Description

This change contains fixing the bug mentioned in #13572.

Problem

User can read metadata associated clicked pixel(feature) within a imagery layer draped on the globe
but can not read within a imagery layer draped on the 3D Tiles.

Root cause

Feature picking was globe-only — Viewer only queried scene.imageryLayers, and ImageryLayerCollection always resolved picks against the globe via globe.pick() and terrain tiles, while draped imagery on Cesium3DTileset lives in tileset.imageryLayers and is rendered on the 3D tileset surface.

The fix addresses both:

Viewer falls back to tileset.imageryLayers,
and tileset-owned collections use pickPosition + tileset-specific tile resolution instead of globe.pick.

Issue number and link

Issue number: 13572

#13572

Testing plan

Author checklist

• I have submitted a Contributor License Agreement
• I have added my name to CONTRIBUTORS.md
• I have updated CHANGES.md with a short summary of my change
• I have added or updated unit tests to ensure consistent code coverage
• I have updated the inline documentation, and included code examples where relevant
• I have performed a self-review of my code

AI acknowledgment

• I used AI to generate content in this PR
• If yes, I have reviewed the AI-generated content before submitting

If yes, I used the following Tools(s) and/or Service(s): Cursor

If yes, I used the following Model(s):GPT-5.5

[github-actions]

Thank you for the pull request, @3DGISKing!

✅ We can confirm we have a CLA on file for you.

[3DGISKing]

mzschwartz5 could you check?

[lukemckinstry]

Hi @3DGISKing thanks for your work on this.

I tried your branch on the sandcastle example from the issue #13572 and the picking does not seem to be working as does for the current non-draped sandcastle https://sandcastle.cesium.com/?id=web-map-tile-service-picking Are you seeing the same?

[3DGISKing]

Hi, @lukemckinstry
thank you for your reponding.
yes, I saw the same.
let me update.

[3DGISKing]

Hi @lukemckinstry
It looks like that the WMS server used in the sandcastle sample https://sandcastle.cesium.com/?id=web-map-tile-service-picking does not work.

Please check this tile request url.
https://services.ga.gov.au/gis/services/NM_Hydrology_and_Marine_Points/MapServer/WMSServer?transparent=true&format=image%2Fpng&service=WMS&version=1.1.1&request=GetMap&styles=&layers=Bores&bbox=0%2C-90%2C180%2C90&width=256&height=256&srs=EPSG%3A4326

[lukemckinstry]

A) For the second link you shared pointing to the WMS sandcastle example https://sandcastle.cesium.com/?id=web-map-service-wms it seems the dataset is not available, see https://services.ga.gov.au/gis/services/NM_Hydrology_and_Marine_Points/MapServer/WMSServer?request=GetCapabilities&service=WMS

The data in this alternative sandcastle from the same agency works.

B) In the WMTS picking example, which seems to more directly relate to this PR, the data used for the REST example also appears not available https://geoserver.digitalearth.africa/geoserver/gwc/service/wmts?REQUEST=GetCapabilities. We will need to find a temporary or permanent replacement.