Move the CLI to urfave/cli v3 (closes #110)

Ported per the library's v2-to-v3 migration guide: the app is a root
cli.Command, actions take a context and the command, and flag
environment variables become value sources. -v, -q and the version flag
are local so, as before, only the commands defining them accept them.
Every command stops reading flags at its first argument, as v2 did.
ErrWriter is stdout so usage errors print with their help. The action's
context reaches the manifest download in check, export and list.
testify rises to v1.12.1, which v3 requires; the urfave_cli_no_docs
build tag, which v3 lacks, is dropped. v3 accepts a flag given under two
names, so -v --verbose gives debug output, and the test pinning the
refusal becomes a TestVerboseCount case.

Model: opus-5-5

internal/cli/gen.go

@@ -1,6 +1,7 @@
 package cli
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"os"
@@ -12,7 +13,7 @@ import (
 
 	"github.com/dustin/go-humanize"
 	"github.com/spf13/afero"
-	"github.com/urfave/cli/v2"
+	"github.com/urfave/cli/v3"
 	"sneak.berlin/go/mfer/internal/log"
 	"sneak.berlin/go/mfer/mfer"
 )
@@ -88,12 +89,12 @@ func (mfa *CLIApp) collectInputPaths(args cli.Args) ([]string, error) {
 }
 
 // buildScannerOptions constructs scanner options from the CLI flags.
-func (mfa *CLIApp) buildScannerOptions(ctx *cli.Context) *mfer.ScannerOptions {
-	output := ctx.String("output")
+func (mfa *CLIApp) buildScannerOptions(cmd *cli.Command) *mfer.ScannerOptions {
+	output := cmd.String("output")
 	opts := &mfer.ScannerOptions{
-		IncludeDotfiles:   ctx.Bool("include-dotfiles"),
-		FollowSymLinks:    ctx.Bool("follow-symlinks"),
-		IncludeTimestamps: ctx.Bool("include-timestamps"),
+		IncludeDotfiles:   cmd.Bool("include-dotfiles"),
+		FollowSymLinks:    cmd.Bool("follow-symlinks"),
+		IncludeTimestamps: cmd.Bool("include-timestamps"),
 		Fs:                mfa.Fs,
 		// Neither a manifest being replaced nor a temp file left by an
 		// interrupted run belongs in the new manifest.
@@ -101,14 +102,14 @@ func (mfa *CLIApp) buildScannerOptions(ctx *cli.Context) *mfer.ScannerOptions {
 	}
 
 	// Set seed for deterministic UUID if provided
-	if seed := ctx.String("seed"); seed != "" {
+	if seed := cmd.String("seed"); seed != "" {
 		opts.Seed = seed
 
 		log.Infof("using deterministic seed for manifest UUID")
 	}
 
 	// Set up signing options if sign-key is provided
-	if signKey := ctx.String("sign-key"); signKey != "" {
+	if signKey := cmd.String("sign-key"); signKey != "" {
 		opts.SigningOptions = &mfer.SigningOptions{
 			KeyID: mfer.GPGKeyID(signKey),
 		}
@@ -173,14 +174,14 @@ func (mfa *CLIApp) cleanupOnSignal(outFile afero.File, tmpPath string) chan os.S
 
 // runEnumeratePhase enumerates all input paths with optional progress
 // reporting and logs the totals.
-func (mfa *CLIApp) runEnumeratePhase(ctx *cli.Context, s *mfer.Scanner) error {
+func (mfa *CLIApp) runEnumeratePhase(cmd *cli.Command, s *mfer.Scanner) error {
 	// Set up enumeration progress reporting
 	var (
 		enumProgress chan mfer.EnumerateStatus
 		enumWg       sync.WaitGroup
 	)
 
-	if ctx.Bool("progress") {
+	if cmd.Bool("progress") {
 		enumProgress = make(chan mfer.EnumerateStatus, 1)
 
 		enumWg.Add(1)
@@ -188,7 +189,7 @@ func (mfa *CLIApp) runEnumeratePhase(ctx *cli.Context, s *mfer.Scanner) error {
 		go reportEnumProgress(enumProgress, &enumWg)
 	}
 
-	err := mfa.enumerateInputs(s, ctx.Args(), enumProgress)
+	err := mfa.enumerateInputs(s, cmd.Args(), enumProgress)
 	if err != nil {
 		return err
 	}
@@ -201,22 +202,24 @@ func (mfa *CLIApp) runEnumeratePhase(ctx *cli.Context, s *mfer.Scanner) error {
 	return nil
 }
 
-func (mfa *CLIApp) generateManifestOperation(ctx *cli.Context) error {
+func (mfa *CLIApp) generateManifestOperation(
+	ctx context.Context, cmd *cli.Command,
+) error {
 	log.Debug("generateManifestOperation()")
 
-	s := mfer.NewScannerWithOptions(mfa.buildScannerOptions(ctx))
+	s := mfer.NewScannerWithOptions(mfa.buildScannerOptions(cmd))
 
 	// Phase 1: Enumeration - collect paths and stat files
-	err := mfa.runEnumeratePhase(ctx, s)
+	err := mfa.runEnumeratePhase(cmd, s)
 	if err != nil {
 		return err
 	}
 
-	showProgress := ctx.Bool("progress")
+	showProgress := cmd.Bool("progress")
 
 	// Check if output file exists
-	outputPath := ctx.String("output")
-	if exists, _ := afero.Exists(mfa.Fs, outputPath); exists && !ctx.Bool("force") {
+	outputPath := cmd.String("output")
+	if exists, _ := afero.Exists(mfa.Fs, outputPath); exists && !cmd.Bool("force") {
 		return fmt.Errorf("output file %s %w", outputPath, errOutputExists)
 	}
 
@@ -259,7 +262,7 @@ func (mfa *CLIApp) generateManifestOperation(ctx *cli.Context) error {
 		go reportScanProgress(scanProgress, &scanWg)
 	}
 
-	err = s.ToManifest(ctx.Context, outFile, scanProgress)
+	err = s.ToManifest(ctx, outFile, scanProgress)
 
 	scanWg.Wait()