Part of
https://linear.app/zed-industries/issue/Z-2750/investigate-performance-of-collaborating-on-large-files-with-inlay

* Declares client capabilities for hint resolution, marking both fields
available for resolution (`textEdits` and `tooltop`) as resolvable.
We do not use these fields anymore, hence can omit resolving them for
now, but LSP servers can omit them during general hint requests.

* Removes `tooltip` and replaces complex `label` with its simple string
counterpart for clients' hint responses from host: both should be
resolved through host later

Release Notes:

- Reduces collab mode clients' inlay hint footprint by enabling hint
data resolution