Dynamic content (Part 3) (#15713)

* Initial version

* Fix lint issues

* Tidy ups and lint fixes

* Add some notes

* Localisations

* Avoid using general 'actions' class name

* Further fixes

* Remove test code

* Address feedback from walk through

* Add test ids and updated e2e tests, fix lint

* Update .gitignore

* Remove dev readme file

* Add simple developer docs, update type comments, bump icon package version number

* Address PR feedback

* Address PR feedback 2nd round

* Fix lint

* Use user id hash in the local storage key

* FIrst version of dynamic content

* Revert merge errors

* Fix merge errors

* Tidy ups, better types and more documentation

* Add support for settings

* Improve docs

* Tidy up config and settings types

* Addm LTS, remove debug content (will do this differently)

* Add unit tests

* Update unis tests

* Fix unit tests

* Tidy ups

* Fix first round of PR feedback and update tests

* Address PR feedback

* FIrst version of dynamic content

* Factor out system info for clearer code

* Add announcement support

* Fixes

* Remove comment for hidden as its not added in this PR

* Fix merge issues

* Ensure mark all read updates via handler as well

* Add unit tests

* Fix comment for unsetValue

Updated comment for unsetValue property in NotificationPreference type.

* Fix lint errors

* Address PR Feedback

* FIrst version of dynamic content

* Tidy ups, better types and more documentation

* Add support for settings

* Improve docs

* Tidy up config and settings types

* Addm LTS, remove debug content (will do this differently)

* Add unit tests

* Update unis tests

* Fix unit tests

* Tidy ups

* Add home page announcements

* Minor updates

* Add support for content on the home page

* Fix merge issues

* Minor tidy ups

* Tidy ups

* Fix bad merge

* Further merge fixes

* Merge fixes

* Mark all as read does not affect hidden items

* Fix unit tests

* Fix lint

* Make use of markdown consistent

* Add aria labels to other buttons

Author: nwmac

shell/assets/images/content/README.md

@@ -0,0 +1,5 @@
+# Built-in icon images that can be used for Dynamic Content
+
+These are referenced in the dynamic content package with the '~' prefix.
+
+Light theme mode images are in this folder. The version of the image for dark theme mode should be in the `dark` sub-folder.