Link views from the zone list, add breadcrumbs and view colours

The view shown in the zone list and on the zone page now links to that
view. The zone page and changeset page get breadcrumbs, and the zone list
keeps its filters in the address so going back restores them. Views can
be given a colour (Views > Edit, `jarl view color`, PUT /views/{id}/color)
so zones of the same view are easy to spot; the colour is UI-only, kept
outside changesets, and needs no deploy.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

cmd/jarl/complete.go

@@ -15,6 +15,7 @@ import (
 	"github.com/spf13/cobra"
 
 	"jarl/internal/api"
+	"jarl/internal/model"
 	"jarl/internal/rr"
 )
 
@@ -71,6 +72,8 @@ func argCompletion(c *cobra.Command) cobra.CompletionFunc {
 			return lookup(cmd, "zone")
 		case p == "VIEW":
 			return lookup(cmd, "view")
+		case p == "COLOR":
+			return append([]string{"default"}, model.ViewColors...), cobra.ShellCompDirectiveNoFileComp
 		case p == "ACL":
 			return lookup(cmd, "acl")
 		case p == "USER":

cmd/jarl/config_cmds.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"io"
 	"net/url"
+	"slices"
 	"strings"
 
 	"github.com/spf13/cobra"
@@ -27,9 +28,9 @@ func viewCmd() *cobra.Command {
 				return err
 			}
 			return output(views, func(w io.Writer) {
-				fmt.Fprintln(w, "#\tID\tVIEW\tMATCH-CLIENTS\tMATCH-DESTINATIONS\tZONES")
+				fmt.Fprintln(w, "#\tID\tVIEW\tMATCH-CLIENTS\tMATCH-DESTINATIONS\tZONES\tCOLOR")
 				for i, v := range views {
-					fmt.Fprintf(w, "%d\t%d\t%s\t%s\t%s\t%d\n", i+1, v.ID, v.Name, orAny(v.MatchClients), orAny(v.MatchDestinations), v.Zones)
+					fmt.Fprintf(w, "%d\t%d\t%s\t%s\t%s\t%d\t%s\n", i+1, v.ID, v.Name, orAny(v.MatchClients), orAny(v.MatchDestinations), v.Zones, orDefault(v.Color))
 				}
 			})
 		},
@@ -172,10 +173,45 @@ func viewCmd() *cobra.Command {
 			return report(resp)
 		},
 	}
-	cmd.AddCommand(list, create, update, del, order)
+	color := &cobra.Command{
+		Use:   "color VIEW COLOR",
+		Short: "Set the colour the web UI shows a view in",
+		Long: "Set the colour the web UI shows a view in, so zones of the same view are easy to spot.\n" +
+			"Colours: default (the link colour), " + strings.Join(model.ViewColors, ", ") + ".\n" +
+			"This only changes the web UI: it applies at once, with no changeset or deploy.",
+		Example: `  jarl view color internal green
+  jarl view color internal default`,
+		Args: cobra.ExactArgs(2),
+		RunE: func(cmd *cobra.Command, args []string) error {
+			c, err := newClient()
+			if err != nil {
+				return err
+			}
+			col := strings.ToLower(args[1])
+			if col == "default" {
+				col = ""
+			} else if !slices.Contains(model.ViewColors, col) {
+				return fmt.Errorf("unknown colour %q: use default, %s", args[1], strings.Join(model.ViewColors, ", "))
+			}
+			var v api.View
+			if err := c.Do(ctx(), "PUT", "/views/"+url.PathEscape(args[0])+"/color", nil, api.ViewColor{Color: col}, &v); err != nil {
+				return err
+			}
+			fmt.Printf("View %s: colour %s\n", v.Name, orDefault(v.Color))
+			return nil
+		},
+	}
+	cmd.AddCommand(list, create, update, del, order, color)
 	return cmd
 }
 
+func orDefault(s string) string {
+	if s == "" {
+		return "default"
+	}
+	return s
+}
+
 func orAny(list []string) string {
 	if len(list) == 0 {
 		return "any"