## What
This (admittedly massive) PR updates the "physical" documentation
structure and fixes url inconsistencies and SEO problems reported by
marketing. The main points are:
- remove or move directories : advanced, user_guide, deploy, api
- move the files contained within to the appropriate one of topics,
how-to, tutorials, or reference
- update internal doc links and product links to the content
- create client-side redirects for all the urls that have changed.
A number of the files have been renamed in small ways to better match
their url and to make them easier to find. Additionally, the top-level
api directory has been moved to /reference/api/legacy/unleash (see the
discussion points section for more on this).
## Why
When moving our doc structure to diataxis a while back, we left the
"physical' files lying where they were, because it didn't matter much to
the new structure. However, that did introduce some inconsistencies with
where you place docs and how we organize them.
There's also the discrepancies in whether urls us underscores or hyphens
(which isn't necessarily the same as their file name), which has been
annoying me for a while, but now has also been raised by marketing as an
issue in terms of SEO.
## Discussion points
The old, hand-written API docs have been moved from /api to
/reference/api/legacy/unleash. There _is_ a /reference/api/unleash
directory, but this is being populated by the OpenAPI plugin, and mixing
those could only cause trouble. However, I'm unsure about putting
/legacy/ in the title, because the API isn't legacy, the docs are. Maybe
we could use another path? Like /old-docs/ or something? I'd appreciate
some input on this.
* refactor: fix splash page button background color
* refactor: regenerate OpenAPI client
* refactor: clean up strategy parameter types
* refactor: remove index signature from IConstraint
* refactor: fix never-seen status in features list
* refactor: remove unused securityLogger
* refactor: port commonStyles to TS
* refactor: port testIds to TS
* refactor: move app.css into themes
* refactor: use absolute import paths
* refactor: port LayoutPicker to TS
* refactor: port routes to TS
* refactor: port ScrollTop to TS
* refactor: update unused/missing ScrollTop exceptions
* refactor: remove unused route flags field
* refactor: change constants ext to TS
* refactor: remove unused testData file
* refactor: port styles to TS
* refactor: wait before typing in auth spec
