Poor trigger characters for the language server

Currently the only registered trigger character for the language server is @: https://github.com/graphql/graphiql/blob/65aa64811ccd40c5e8ba99edec825a91115a3c8b/packages/graphql-language-service-server/src/MessageProcessor.ts#L168

I think there are many cases when automatically triggering completions would be beneficial. For example when typing { to select fields of an object or when typing ( after field name to specify the arguments to pass). None of those currently trigger auto-completion which means that the user has to trigger it manually with a shortcut.

[rchl]

I’m a LSP client developer for ST so I “more or less” know how those things work.

additionalTextEdits can do various edits to the document when completion is committed but my initial issue is about showing the completions in the first place since they are not shown.

When mentioning triggerCharacters I meant those in context of the completionProvider.triggerCharacters server capability and not in context of individual completion.

[rchl]

Also:

• $ - in query($arg: String!), for example