This commit adds support in the Ivy Language Service for autocompletion in a
global context - e.g. a {{foo|}} completion.
Support is added both for the primary function `getCompletionsAtPosition` as
well as the detail functions `getCompletionEntryDetails` and
`getCompletionEntrySymbol`. These latter operations are not used yet as an
upstream change to the extension is required to advertise and support this
capability.
PR Close#39250
Alex Rickabaugh