v3 fish completions conflate 2+ level subcommand options

[bittrance]

My urfave/cli version is

c6c5804

Checklist

• Are you running the latest v3 release? The list of releases is here.
• Did you check the manual for your release? The v3 manual is here
• Did you perform a search about this problem? Here's the GitHub guide about searching.

Describe the bug

Where a command has identical L2 sub-commands, we will suggest the union of their options.

To reproduce

	app := &cli.Command{
		Name:                  "mycli",
		Version:               "1.0.0",
		Usage:                 "Pure awesomeness.",
		EnableShellCompletion: true,
		Suggest:               true,
		Commands: []*cli.Command{
			{
				Name:  "more-awesome",
				Usage: "Become awesomer!",
				Action: func(ctx context.Context, cmd *cli.Command) error {
					return nil
				},
				Commands: []*cli.Command{
					{
						Name: "set",
						Flags: []cli.Flag{
							&cli.IntFlag{
								Name:     "increase",
								Required: true,
							},
						},
					},
				},
			},
			{
				Name:  "less-awesome",
				Usage: "Humility",
				Action: func(ctx context.Context, cmd *cli.Command) error {
					return nil
				},
				Commands: []*cli.Command{
					{
						Name: "set",
						Flags: []cli.Flag{
							&cli.IntFlag{
								Name:     "decrease",
								Required: true,
							},
						},
					},
				},
			},
		},
	}

Observed behavior

$ mycli more-awesome set --
--decrease  --help  (show help)  --increase

Expected behavior

L2 sub-commands should suggest their own options only.

Want to fix this yourself?

The fix is to tell complete about the full sub-command "path". Should be straight-forward given the Lineage() method on commands. PR pending.

Run go version and paste its output here

go version go1.23.8 linux/amd64

Run go env and paste its output here

GO111MODULE=''
GOARCH='amd64'
GOBIN=''
GOCACHE='/home/andqvi/.cache/go-build'
GOENV='/home/andqvi/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/home/andqvi/go/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/home/andqvi/go'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/home/andqvi/go/pkg/mod/golang.org/toolchain@v0.0.1-go1.23.8.linux-amd64'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/home/andqvi/go/pkg/mod/golang.org/toolchain@v0.0.1-go1.23.8.linux-amd64/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.23.8'
GODEBUG=''
GOTELEMETRY='local'
GOTELEMETRYDIR='/home/andqvi/.config/go/telemetry'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/home/andqvi/projects/external/harness-cli/go.mod'
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 -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build320049062=/tmp/go-build -gno-record-gcc-switches'