Improve performance of language server

[per1234]

Describe the current behavior

Declaring a function and writing an invocation fast enough doesn't show that function in the autocomplete window right away

Describe the request

Results are updated more quickly.

Desktop

• Language Server version: 0.6.0
• CLI version: 0.20.2
• OS: Windows 10

Additional context

Originally reported at #46 (comment)

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