Map context: fix WMTS layer extent

[fgravin]

A the moment, the extent used to zoom on a WMTS layer is the tilegrid extent, extracted by Openlayers from the getCapabilities informations. It's generally the projection world extent.

The idea is to get the accurate extent of the layer from the capabilities itself, and use it if any.

Sponsored by SwissTopo geocat.ch

[github-actions]

Affected libs: feature-map, feature-dataviz, feature-record, feature-router,
Affected apps: metadata-editor, datahub, demo, webcomponents, search, map-viewer,

• 🚀 Build and deploy storybook and demo on GitHub Pages
• 📦 Build and push affected docker images

[coveralls]

coverage: 85.453% (+3.5%) from 81.942%
when pulling 206676f on fix-extent
into 19be416 on main.

[jahow]

looks good enough for now, thanks :)