Manage notification channels instead of an ntfy topic

Mirrors the server's channels API: add/remove channels per user from the Users
section. Requires the matching server release.

Claude-Session: https://claude.ai/code/session_016mBLURvJoMuUEr9cB2RpUN

internal/tui/model_test.go

@@ -1,6 +1,7 @@
 package tui
 
 import (
+	"strings"
 	"testing"
 	"time"
 
@@ -196,29 +197,32 @@ func TestAlertRows_ShowIncidentLink(t *testing.T) {
 	}
 }
 
-// A user with no ntfy topic gets no pages of their own — the row has to say so
+// A user with no channel gets no pages of their own — the row has to say so
 // rather than leaving a blank that reads as "not loaded yet".
-func TestUserManageRows_ShowMissingTopic(t *testing.T) {
-	topic := "terdut-niklas"
-	empty := ""
+func TestUserManageRows_ShowMissingChannels(t *testing.T) {
 	m := NewModel(nil, "http://test", time.Minute, theme.GruvboxDark)
 	m.width, m.height = 120, 40
 	m.users = []api.User{
-		{ID: 1, Username: "niklas", NtfyTopic: &topic},
+		{ID: 1, Username: "niklas", Channels: []api.NotificationChannel{
+			{ID: 1, Type: "ntfy", Address: "terdut-niklas", Enabled: true}}},
 		{ID: 2, Username: "alex"},
-		// The server stores a blank topic as NULL, but a stale client or an older
-		// server can still hand one back; it means the same thing.
-		{ID: 3, Username: "sam", NtfyTopic: &empty},
+		{ID: 3, Username: "sam", Channels: []api.NotificationChannel{
+			{ID: 2, Type: "ntfy", Enabled: false}}},
 	}
 	m.rebuildUserManageTable()
 
 	rows := m.userManageTable.Rows()
-	if rows[0][2] != "terdut-niklas" {
-		t.Errorf("expected the topic in the row, got %q", rows[0][2])
+	if rows[0][2] != "ntfy" {
+		t.Errorf("expected the channel kind in the row, got %q", rows[0][2])
 	}
-	if rows[1][2] != "—" || rows[2][2] != "—" {
-		t.Errorf("expected an em dash for nil and empty topics, got %q and %q",
-			rows[1][2], rows[2][2])
+	if strings.Contains(rows[0][2], "terdut-niklas") {
+		t.Errorf("the row must not carry an address, got %q", rows[0][2])
+	}
+	if rows[1][2] != "—" {
+		t.Errorf("expected an em dash for a user with no channel, got %q", rows[1][2])
+	}
+	if rows[2][2] != "ntfy (off)" {
+		t.Errorf("expected a switched-off channel to say so, got %q", rows[2][2])
 	}
 }
 
@@ -228,7 +232,7 @@ func TestUserManageRows_ShowMissingTopic(t *testing.T) {
 func TestColumnWidthsFitTheTerminal(t *testing.T) {
 	for _, width := range []int{100, 110, 140, 200} {
 		// Five cells each, or six once a Team column is added. userManageColumns
-		// is five cells as well: username, email, topic, flags, created.
+		// is five cells as well: username, email, channels, flags, created.
 		for name, tc := range map[string]struct {
 			cols  []table.Column
 			cells int