Support component auto-completion while editing template

[沈青川]

Requirement description

Let's see the usage example below:

function Comp() {
  return vine`
    <|
    // ^ Cursor is here and waiting for input a component name 
    // No matter if it is a Vine component or a SFC based component, as long as a valid Vue component.
  `
}

We'd like to provide a list of components that resolved by language service here in VSCode.