feat: ember specific data utils

[runspired]

Adds @warp-drive/ember to assist with consuming requests from EmberData in components.

For the full motivations, read https://github.com/emberjs/data/blob/feat-ember/packages/ember/README.md

Note: We still recommend data being loaded by routes (or a future route replacement) to minimize potential for waterfalls and to provide the ability to hoist the data-fetch tree out of the render tree. We're considering at some point providing something along the lines of @warp-drive/router as an alternative to Ember's default router that enables more advanced data-fetch paradigms, and applications that continue to use the routing paradigm as their primary fetch paradigm today will find it easier to take advantage of the benefits this offers once it becomes available.

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TODO (follow up PRs ok)

• Test: if no cancelled block is present, abort may be handled by error block
• Test/~Impl: if no error block is present, non-abort-error is rethrown
• Test/Impl: cancelled block exposes state with retry function
• Test/Impl: error block exposes state with retry function
• Test/Impl: content block exposes state with refresh function
• Test/Impl: content block exposes state with reload function
• Test/Impl: content block exposes state with isRefreshing property
• Test/Impl: content block exposes state with abort function when isRefreshing is true
• Test/Impl: content block exposes state with latestRequest
• Test/Impl: @Autorefresh enables automatic refresh after background resume
• Test/Impl: @autorefreshThreshold enables configuration of amount of time in background required before autorefresh will be attempted on resume
• Test/Impl: @autorefreshBehavior allows 'refresh' 'reload' and 'policy'