For the details about this PR, please see the blog post https://eed3si9n.com/sbt-remote-cache/.
* Add cache basics
* Refactor Attributed to use StringAttributeMap, which is Map[StringAttributeKey, String]
* Implement disk cache
* Rename Package to Pkg
* Virtualize packageBin
* Use HashedVirtualFileRef for packageBin
* Virtualize compile task
Problem
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In sbt 1, platform cross building is implemented using in the user-land
using `%%%` operator, which clevery handles both Scala cross building
and appending platform suffix like sjs1.
However, in general symbolic `%%%` is confusing, and hard to explain.
Solution
--------
In sbt 2, we should subsume the idea of platform cross building,
so `%%` can act as the current `%%%` operator.
This adds a new setting called `platform`, which defaults to
`Platform.jvm` by default.
When a subprojects sets it to `Platform.sjs1`, `ModuleID`s defined using
`%%` operator will inject the platform suffix `_sjs1` **in addition**
to the Scala binary suffix `_2.13` etc.
Note: Explicit JVM dependencies will now require `.platform(Platform.jvm)`.
Launcher 1.4.1 is capable of launching Scala 3 apps.
In other words, launchers prior to 1.4.1 are not capable of
launching Scala 3 apps, including tests for sbt 2.x.
This removes OkHttp dependency.
This also removes an experimental feature to customize HTTP for Ivy called
CustomHttp we added in sbt 1.3.0.
Since LM got switched to Coursier in 1.3.0, I don't think we advertized
CustomHttp.