feat(label): address labels by name and add import and clone

label edit bug and label delete kind/feature failed with "invalid resource
number", and label create took its name as --name and required
--color. Like gh, label create takes the name as an argument and picks
a random color without -c; label edit and delete take names or IDs
(delete several at once, after a confirmation that names them), and
-c/-d/-n/-f are the gh short flags. Without a name on a terminal, label
create asks for the name, color and description.

label list shows ID NAME COLOR DESCRIPTION FLAGS with a colored swatch
and exclusive and archived labels flagged. Mutations report ✓ lines.
label import reads a label file or stdin (label create --file still
works), label clone copies another repository's labels, skipping those
that exist unless --force, and label export writes to stdout by default
or to -O/--output.

Signed-off-by: bircni <bircni@icloud.com>

internal/services/label_selection.go

@@ -25,23 +25,41 @@ func (s Labels) finder(byName bool) NameOrID[Label] {
 	return NameOrID[Label]{Kind: "label", Scope: s.Scope(), ID: func(l Label) int64 { return l.ID }, Name: func(l Label) string { return l.Name }, ByName: byName}
 }
 
+// Find returns the labels of the scope that raws address, each by ID or name (D10); byName matches
+// numeric values as names only.
+func (s Labels) Find(ctx context.Context, raws []string, byName bool) ([]Label, error) {
+	items, err := s.All(ctx)
+	if err != nil {
+		return nil, err
+	}
+	result := make([]Label, len(raws))
+	for i, raw := range raws {
+		if result[i], err = s.finder(byName).Find(items, raw); err != nil {
+			return nil, err
+		}
+	}
+	return result, nil
+}
+
 // CreateUnique creates a label unless existing, the labels of the scope, has one with its name,
 // ignoring case. Then update edits that label with the supplied fields, keeping its name, and
 // otherwise CreateUnique fails: Gitea would create a second label that name filters cannot tell
-// apart.
-func (s Labels) CreateUnique(ctx context.Context, existing []Label, opts LabelOptions, update bool) (Label, error) {
+// apart. It reports whether it updated a label.
+func (s Labels) CreateUnique(ctx context.Context, existing []Label, opts LabelOptions, update bool) (Label, bool, error) {
 	current, err := s.finder(true).Find(existing, deref(opts.Name))
 	if errors.As(err, new(*NotFoundError)) {
-		return s.Create(ctx, opts)
+		label, err := s.Create(ctx, opts)
+		return label, false, err
 	}
 	if err != nil {
-		return Label{}, err
+		return Label{}, false, err
 	}
 	if !update {
-		return Label{}, &ConflictError{Reason: ReasonExists, Kind: "label", Key: strconv.Quote(current.Name), Scope: s.Scope(), Hint: "pass --force to update it"}
+		return Label{}, false, &ConflictError{Reason: ReasonExists, Kind: "label", Key: strconv.Quote(current.Name), Scope: s.Scope(), Hint: "pass --force to update it"}
 	}
 	opts.Name = nil
-	return s.Edit(ctx, current.ID, opts)
+	label, err := s.Edit(ctx, current.ID, opts)
+	return label, true, err
 }
 
 func selectLabelNames(scope string, names []string, matches map[string][]int64) ([]int64, error) {