[Feature] yarn plugin remove / friendlier error message for missing plugins

• I'd be willing to implement this feature
• This feature can already be implemented through a plugin

Describe the user story

Looks like the latest berry now ships with the workspace-tools plugin already bundled.

After updating, I started running into errors such as:

yarn workspace workspace1 build-release
Ambiguous Syntax Error: Cannot find who to pick amongst the following alternatives:

  0. yarn workspace <workspaceName> <commandName> ...
  1. yarn workspace <workspaceName> <commandName> ...

While running workspace workspace1 build-release

With some help on discord, I found out about that this could happen because the plugin is duplicated between core and the separately installed one.

I looked for a way to remove the plugin, but the documentation doesn't mention what to do, so I attempted to delete the file from .yarn/plugins, which led to the following error afterwards when running any yarn command:

$ yarn
Internal Error: Cannot find module '/home/.../.yarn/plugins/@yarnpkg/plugin-workspace-tools.js'
Require stack:
- /home/.../.yarn/releases/yarn-sources.js
Require stack:
- /home/.../.yarn/releases/yarn-sources.js

I found the plugin referenced in .yarnrc.yml and also removed it from there, which got yarn working again.

Describe the solution you'd like

It would be nice if a command to remove a plugin was available, perhaps yarn plugin remove workspace-tools. With yarn installed globally it may be even harder to figure out how to remove plugins.

Additionally, a friendlier error message than the cannot find module would be nice. Perhaps one that would point to .yarnrc.yml so users know how to resolve it.

Describe the drawbacks of your solution

Can't think of any.

Describe alternatives you've considered

Can be solved manually, but the experience is confusing.

The report points to .yarnrc.yml, .yarn/plugins, and .yarn/releases/yarn-sources.js; begin by tracing how the duplicate workspace-tools plugin and missing plugin reference produce the reported errors. Use the shown yarn plugin, yarn workspace, and yarn commands to reproduce the behavior; done means a plugin removal command exists and missing plugins produce guidance that identifies the configuration to fix.