[bug] Support of alias and Sling Mappings

[nhirrle]

Describe the bug
It seems like sling:alias and mappings are not supported with AEM SPA.
I don't know if this ticket should be rather a feature request than a bug ticket but as it is core functionality in AEM I reported it as a bug.

Package version
All version

To Reproduce
Steps to reproduce the behavior:

1. Add Sling alias on any SPA page. For my example I installed https://github.com/adobe/aem-guides-wknd-spa and add an alias on the homepage http://localhost:4502/editor.html/content/wknd-spa-react/us/en/home.html
   
2. Open the homepage with the alias http://localhost:4502/content/wknd-spa-react/us/en/alias.html?wcmmode=disabled
3. See that no data is rendered

Expected behavior
Data should still be rendered.

Screenshots
Not applicable

Additional context
This has been reported as a ticket in the archived repo adobe/aem-spa-project-archetype#86 but it was never closed.

[lezzowski]

It's unbelievable that after more than one year we have legit no info about it, no one thought to even give a look or leave a comment. Common Adobe modus operandi 😊