feat: Add getDefinitionAtPosition

[Quramy]

What

Add "Go to Definition" feature for fragment spread.

For example, in VSCode, user trigger "Go to definition" (F12 key by default) when the cursor is at the following (A) position, this feature navigates the cursor to (B).

const query = graphql`
  query AppQuery {
     ...AppFragment
##      ^
##      (A) Cursor
  }
`;

const fragment = graphql`
  fragment AppFragment on Query {
##         ^
##         (B) Definition location
    __typename
  }
`

Limitations

This feature depends on global fragment registry.

If users do not turn on enabledGlobalFragments, they can't use this feature.
But I don't think it's a problem. Disabling global fragments means that reference to fragment between multiple template expression requires interpolation. And the explicit interpolation indicates where the fragment definition is located.

[codecov]

Codecov Report

Attention: Patch coverage is 95.28302% with 5 lines in your changes are missing coverage. Please review.

Project coverage is 96.59%. Comparing base (b2721bd) to head (6ed82f8).
Report is 29 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1248      +/-   ##
==========================================
- Coverage   96.62%   96.59%   -0.03%     
==========================================
  Files          73       75       +2     
  Lines        5740     5845     +105     
  Branches      856     1143     +287     
==========================================
+ Hits         5546     5646     +100     
- Misses        192      193       +1     
- Partials        2        6       +4     

Files	Coverage Δ
src/gql-ast-util/fragment-registry.ts	96.64% <100.00%> (+0.03%)	⬆️
...e-service-adapter/get-definition-and-bound-span.ts	100.00% <100.00%> (ø)
...uage-service-adapter/get-definition-at-position.ts	100.00% <100.00%> (ø)
...ervice-adapter/graphql-language-service-adapter.ts	96.77% <100.00%> (+0.64%)	⬆️
...c/language-service-plugin/plugin-module-factory.ts	97.75% <100.00%> (+0.05%)	⬆️
src/graphql-language-service-adapter/types.ts	0.00% <0.00%> (ø)

... and 4 files with indirect coverage changes