x/tools/gopls: detect tools.go files, and suppress warning

I've been looking for a way to fix this for quite a bit of time and nothing I've tried has worked. I'm using oapi-codegen to generate boilerplate for my webserver. The authors of this library recommend the tools.go pattern for managing the dependency, so that go.mod can act as the single source of truth for versioning. For transparency, their readme recommends this here. Doing this actually works -- I can run go generate just fine and my code builds. However, VSCode insists on showing an error and warning in this tools.go file, marking the file and the module folder red:

This is driving me crazy. I'd like to at least suppress these, but I can't find any way to do so. I've tried using the lintFlags to exclude it, but it appears to be gopls and not staticcheck, so this doesn't do anything. I can't find a gopls configuration setting that will allow me to ignore this file or any issues with it, either.

For what it's worth, someone else noticed the same thing with a different library in this issue.

What version of Go, VS Code & VS Code Go extension are you using?

• Run go version to get version of Go from the VS Code integrated terminal.
  • go version go1.22.5 darwin/arm64
• Run gopls -v version to get version of Gopls from the VS Code integrated terminal.
  • golang.org/x/tools/gopls v0.16.1
• Run code -v or code-insiders -v to get version of VS Code or VS Code Insiders.
  • Version: 1.92.1
• Check your installed extensions to get the version of the VS Code Go extension
  • v0.42.0
• Run Ctrl+Shift+P (Cmd+Shift+P on Mac OS) > Go: Locate Configured Go Tools command.

# Tools Configuration


## Environment

GOBIN: undefined
toolsGopath: 
gopath: /Users/[username]/go
GOROOT: /opt/homebrew/Cellar/go/1.22.5/libexec
PATH: /opt/homebrew/bin:/opt/homebrew/sbin:/usr/local/bin:/System/Cryptexes/App/usr/bin:/usr/bin:/bin:/usr/sbin:/sbin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/local/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/bin:/var/run/com.apple.security.cryptexd/codex.system/bootstrap/usr/appleinternal/bin:/Users/[username]/Library/Application Support/JetBrains/Toolbox/scripts:/Users/[username]/go/bin

## Tools

	go:	/opt/homebrew/bin/go: go version go1.22.5 darwin/arm64

	gopls:	/Users/[username]/go/bin/gopls	(version: v0.16.1 built with go: go1.22.5)
	gotests:	not installed
	gomodifytags:	not installed
	impl:	not installed
	goplay:	not installed
	dlv:	/Users/[username]/go/bin/dlv	(version: v1.23.0 built with go: go1.22.5)
	staticcheck:	/Users/[username]/go/bin/staticcheck	(version: v0.4.7 built with go: go1.22.5)

## Go env

Workspace Folder (point-system): /Users/[username]/Documents/Repositories/point-system

	GO111MODULE=''
	GOARCH='arm64'
	GOBIN=''
	GOCACHE='/Users/[username]/Library/Caches/go-build'
	GOENV='/Users/[username]/Library/Application Support/go/env'
	GOEXE=''
	GOEXPERIMENT=''
	GOFLAGS=''
	GOHOSTARCH='arm64'
	GOHOSTOS='darwin'
	GOINSECURE=''
	GOMODCACHE='/Users/[username]/go/pkg/mod'
	GONOPROXY=''
	GONOSUMDB=''
	GOOS='darwin'
	GOPATH='/Users/[username]/go'
	GOPRIVATE=''
	GOPROXY='https://proxy.golang.org,direct'
	GOROOT='/opt/homebrew/Cellar/go/1.22.5/libexec'
	GOSUMDB='sum.golang.org'
	GOTMPDIR=''
	GOTOOLCHAIN='auto'
	GOTOOLDIR='/opt/homebrew/Cellar/go/1.22.5/libexec/pkg/tool/darwin_arm64'
	GOVCS=''
	GOVERSION='go1.22.5'
	GCCGO='gccgo'
	AR='ar'
	CC='cc'
	CXX='c++'
	CGO_ENABLED='1'
	GOMOD='/dev/null'
	GOWORK=''
	CGO_CFLAGS='-O2 -g'
	CGO_CPPFLAGS=''
	CGO_CXXFLAGS='-O2 -g'
	CGO_FFLAGS='-O2 -g'
	CGO_LDFLAGS='-O2 -g'
	PKG_CONFIG='pkg-config'
	GOGCCFLAGS='-fPIC -arch arm64 -pthread -fno-caret-diagnostics -Qunused-arguments -fmessage-length=0 -ffile-prefix-map=/var/folders/by/cxzl4qc57c3c8dd9p9snhn680000gn/T/go-build3419525479=/tmp/go-build -gno-record-gcc-switches -fno-common'

Share the Go related settings you have added/edited

{
    "go.lintTool": "staticcheck",
    "go.lintFlags": [
        "-exclude=gateway/tools/tools.go"
    ]
}