Query for nearest parent block around the hint to resolve

[SomeoneToIgnore]

This way, parameter hints will be found for resolution and #15522 (comment) will be fixed

Hopefully that also helps with whatever else (lifetimes', etc.) hints in
#13962

hints are resolved by querying for textDocument/inlayHint with hint's position turned into a [position-1, position+1] range (instead of the original, much wider document range).

This might lead to issues in the future, with e.g. lifetime hints (currently there's nothing to resolve for them and it's fine) that belong to a certain position, but need to have textDocument/inlayHint query for much bigger range than their position+/-1

[Veykril]

@bors r+

[bors]

📌 Commit 8ae42b5 has been approved by Veykril

It is now in the queue for this repository.

[bors]

⌛ Testing commit 8ae42b5 with merge 3aa6306...

[bors]

☀️ Test successful - checks-actions
Approved by: Veykril
Pushing 3aa6306 to master...

[bors]

☀️ Test successful - checks-actions
Approved by: Veykril
Pushing 3aa6306 to master...

[bors]

👀 Test was successful, but fast-forwarding failed: 422 Changes must be made through a pull request.