feat!: spectrum 2

BREAKING CHANGE: Merges Express and Spectrum to create Spectrum 2

Author: pfulton

README.md

@@ -260,3 +260,40 @@ To spin up the [documentation site](http://opensource.adobe.com/spectrum-css/) l
 ```sh
 yarn dev
 ```
+
+Version numbers are automatically determined, changelogs generated, and packages published.
+
+### Releasing the website
+
+After performing a release, run the following command to release the website:
+
+```shell
+yarn release:docs
+```
+
+### Publishing prereleases
+
+Occasionally, it can be helpful for our subscribers to test CSS changes before they're considered ready to be part of a stable release. To facilitate this, we can publish prerelease versions.
+
+To publish prerelease versions:
+
+- First, be sure that you're working on a branch other than `main`.
+- Once your change(s) are ready to be committed, be aware of the severity of the change(s), and be sure to author your commit message so that Lerna understands how to increase the version number(s) of the affected components.
+- Once your changes are committed, you **must** build the affected package(s) locally **before** publishing them to npm. An npm task for cleaning, building, and beta publishing is available, and it can be run via the following command: `yarn release:beta-from-package`. This command will perform a full `clean` (via the `clean` task), a full `build` (via the `build` task), and will attempt to bump the version numbers in the affected package(s) (via `lerna publish --conventional-prerelease --preid beta --pre-dist-tag beta --no-private`).
+- Depending on the severity of your change(s), and before publishing to npm, Lerna should show a preview of the affected package version numbers that look something like: `@spectrum-css/tag: 3.3.8 => 3.3.9-beta.0`. Additionally, at this time, Lerna will ask if you would like to continue with publishing the changes or cancel.
+- Selecting `y` to publish will publish the affected package(s) to npm.
+
+### Manual prerelease versioning & publishing
+
+Occasionally, you may want to run a prerelease for an individual package and skip a version bump for consuming packages. It's possible to manually change a package's version number to achieve this.
+
+- For the package that you want to prerelease, manually alter the version number in the package's `package.json` file.
+  - For example, let's say you'd like to release a `beta` version of the Switch component. In the Switch's `package.json`, manually change the `version` number from its current number (`"version": "1.0.23"`) to the next appropriate semver version number (`"version": "2.0.0-beta.0"`).
+- Save your changes, and commit them with the appropriate conventional commit-style commit message: `chore(switch): manual version bump for beta release` or something similar.
+- You **must** run a build **before** continuing with the prerelease. An npm task for cleaning, building, and beta publishing is available, and it can be run via the following command: `yarn release:beta-from-package`. This command will perform a full `clean` (via the `clean` task), a full `build` (via the `build` task), and will attempt to publish the package (via `lerna publish --conventional-prerelease --preid beta --pre-dist-tag beta --no-private`).
+- Depending on the severity of your change(s), and before publishing to npm, Lerna should show a preview of the affected package version number that looks something like: `@spectrum-css/switch: 1.0.23 => 2.0.0-beta.0`. Additionally, at this time, Lerna will ask if you would like to continue with publishing the changes or cancel.
+- Selecting `y` to publish will publish the affected package(s) to npm.
+
+## Spectrum 2
+
+More information coming soon!