Switch to `gen-lsp-types` crate to provide LSP types (#24894)
## Summary
[gen-lsp-types](https://github.com/ribru17/gen-lsp-types) is an
alternative to the lsp-types crate, with types generated via codegen
from the official LSP Metamodel for correctness and completeness.
lsp-types issues fixed in gen-lsp-types:
- https://github.com/gluon-lang/lsp-types/issues/310
- https://github.com/gluon-lang/lsp-types/issues/308
- https://github.com/gluon-lang/lsp-types/issues/284
- https://github.com/gluon-lang/lsp-types/issues/278
- https://github.com/gluon-lang/lsp-types/issues/277
- https://github.com/gluon-lang/lsp-types/issues/260
- https://github.com/gluon-lang/lsp-types/issues/245
- https://github.com/gluon-lang/lsp-types/issues/93
## Test Plan
All affected test fixtures updated. Most (all?) are just field
reordering, struct type name renaming
