Adding tooling links using new /to/ format (#10765)

The links added here will be used from various locations that need
consistently functional links that are sometimes manually copy and
pasted. The current set includes links the `flutter` tool, DevTools, the
VS Code plugin(s), the Flutter framework, as well as some surrounding
documentation.

It's particularly important to have these links for areas relying on
fragments, as those redirects can't happen on the server side, and
developers may continue to run SDKs or tools with old links long after
their destination needs to change.

After this PR, `/go/<design-doc>` should only be used for design docs
going forward. Only one item long, top-level redirects such as
`docs.flutter.dev/<top-level>` should also be avoided from now on.

Once this lands, I will update the tools where necessary and land
documentation in the `flutter/flutter` repository that ensures this
format of link is considered.

Contributes to #10363