fix(check/lsp): fall back to @types/* packages if npm package doesn't have types

[nathanwhit]

Fixes #27569.
Fixes #27215.

This PR makes it so type resolution falls back to looking for definitely typed packages (@types/foo) if a given NPM package does not contain type declarations.

One complication is choosing which version of the @types/* package to use, if the project depends on multiple versions. The heuristic here is to try to match the major and minor versions, falling back to the latest version. So if you have

@types/foo: 0.1.0, 0.2.0, 3.1.0, 3.1.2, 4.0.0
foo: 3.1.0

we would choose @types/[email protected] when resolving types for foo.

---

Note that this only uses @types/ packages if you already depend on them. So a follow up to this PR could be to add a diagnostic and quickfix to install @types/foo if we don't find types for foo.

[nayeemrmn]

Is this behaviour gone? Makes sense we don't need it anymore. If so the implementation revolving around

deno/cli/lsp/tsc.rs

Line 3728 in 772fffe

new_deno_types_specifier: Option<String>,

should be removed

[nathanwhit]

Yeah it doesn't trigger anymore because it just uses the @types package automatically. I'll remove that bit

[nayeemrmn]

I guess that snippet was more relevant to

deno/tests/integration/lsp_tests.rs

Lines 8517 to 8519 in d969c59

	#[test]
	#[timeout(300_000)]
	fn lsp_npm_auto_import_with_deno_types() {

. It should be unsupported for auto-imports as well I think.

[dsherret]

LGTM

[felipecrs]

Note that this only uses @types/ packages if you already depend on them.

What does that mean exactly? If I already had the @types/ package as dependency, then why would I need this feature?

[sant123]

@felipecrs with this deno.json:

{
  "imports": {
    "@types/react": "npm:@types/react@^19.0.10",
    "react": "npm:react@^19.0.0"
  }
}

And prior version 2.2.1 types will not work in LSP:

However once you update it to 2.2.1 you get:

[sant123]

@nathanwhit you are the best, thank you so much!

[felipecrs]

Makes total sense. Thanks a ton!

[nathanwhit]

Yup that's correct. I'm separately planning on a diagnostic + quick fix in the LSP for when you don't have the @types package installed (#28216)