Switch to <AngleBracket /> built-in components on Octane branch (input, link-to, etc)

[chancancode]

It's time to switch the Octane guides to use built-in components!

• {{link-to}} -> <LinkTo />
• {{input}} -> <Input />
• {{textarea}} -> <Textarea />

This should mostly just be a syntactic change, but we could also take the opportunity to adjust the flow, remove legacy concepts, etc. For example, since angle bracket invocation takes HTML attributes, we can update the examples to pass them directly (i.e. class= instead of @class=).

To help out, please leave a comment to "claim" the item (🔒 below) so others know not to duplicate the effort! It's fine to claim the item before you have a PR ready (but please release it if it turns out you didn't have the time to do it). Branch from the octane branch of the Guides and open your PR to be merged back into octane. Thank you!

Some resources:

• See PR Angle bracket <BuiltIn /> components #681 for an example
• RFC #459 for details about the feature
• API docs PR

Guides that need to be updated:

• components/actions-and-events.md (:lock: @alexBaizeau Update docs for the built-in components for components/actions-and-events.md #697)
• models/index.md (🔒 @chancancode Angle bracket <BuiltIn /> components #681)
• routing/defining-your-routes.md (🔒 @chancancode Angle bracket <BuiltIn /> components #681 Follow-up to #681 #693)
• routing/preventing-and-retrying-transitions.md (🔒 @chancancode Angle bracket <BuiltIn /> components #681)
• routing/query-params.md (:lock: @alexBaizeau Update docs for the built-in components in routing/query-params.md #698)
• routing/specifying-a-routes-model.md (:lock: @Charizard Update docs for the built-in components for routing/specifying-a-routes-model.md #699)
• templates/binding-element-attributes.md (🔒 @chancancode Angle bracket <BuiltIn /> components #681)
• templates/input-helper.md (:lock: @ddoria921 Update input helpers page #696)
• templates/links.md (🔒 @chancancode Angle bracket <BuiltIn /> components #681)
• testing/testing-components.md (:lock: @Charizard Update docs for the built-in components for testing components page #700)
• tutorial/auto-complete-component.md (:lock: @zachgarwood Angle-bracket-ize tutorial/autocomplete-component.md #702)
• tutorial/model-hook.md (:lock: @mdbiscan Update docs for the built-in components for model-hook page #704)
• tutorial/routes-and-templates.md (:lock: @claytonturner Update docs for the built-in components for tutorial/routes-and-templ… #705)
• tutorial/simple-component.md (:lock: @mdbiscan Update docs for the built-in components for simple-component page #706)
• tutorial/subroutes.md (:lock: @dknutsen Update subroute guides to use angle bracket built-ins #707)
• upgrading/editions.md (:lock: @mdbiscan Updating upgrading editions.md #709)

[alexBaizeau]

I'm claiming components/actions-and-events.md

[alexBaizeau]

I'm claiming routing/query-params.md

[Charizard]

Would like to claim routing/specifying-a-routes-model.md

[Charizard]

Would like to claim testing/testing-components.md