refactor: move more commands to internal/cmd (#207)

* refactor: move more commands to internal/cmd

Part of https://github.com/ooni/probe/issues/1335.

We would like all commands to be at the same level of engine
rather than inside engine (now that we can do it).

* fix: update .gitignore

* refactor: also move jafar outside engine

* We should be good now?

internal/engine/cmd/oohelperd/internal/dns.go

@@ -1,32 +0,0 @@
-package internal
-
-import (
-	"context"
-	"sync"
-
-	"github.com/ooni/probe-cli/v3/internal/engine/experiment/webconnectivity"
-	"github.com/ooni/probe-cli/v3/internal/engine/netx"
-	"github.com/ooni/probe-cli/v3/internal/engine/netx/archival"
-)
-
-// newfailure is a convenience shortcut to save typing
-var newfailure = archival.NewFailure
-
-// CtrlDNSResult is the result of the DNS check performed by
-// the Web Connectivity test helper.
-type CtrlDNSResult = webconnectivity.ControlDNSResult
-
-// DNSConfig configures the DNS check.
-type DNSConfig struct {
-	Domain   string
-	Out      chan CtrlDNSResult
-	Resolver netx.Resolver
-	Wg       *sync.WaitGroup
-}
-
-// DNSDo performs the DNS check.
-func DNSDo(ctx context.Context, config *DNSConfig) {
-	defer config.Wg.Done()
-	addrs, err := config.Resolver.LookupHost(ctx, config.Domain)
-	config.Out <- CtrlDNSResult{Failure: newfailure(err), Addrs: addrs}
-}