feat: remove non-indexed dependencies and packages
Created by: sqs
This removes the code paths that query a language server for workspace/xdependencies
and workspace/xpackages
. It retains the global-reference-indexing code paths. The removed code paths are no longer used (they were only used by the repository graph area), and they do not make sense in a world where language support comes from Sourcegraph extensions.
BREAKING CHANGE: No known GraphQL API clients use these resolvers.