Add the setup flow's confirm screen

What the answers switch on is read off the registry's derivation and
never computed here, so the list the person confirms is the list the
completion route writes. Units, language and time zone are shown once
beside it, changeable in Settings, never asked again.

The profile half keeps the baseline form and its per-field refusals:
the fields are seeded from the account so a value it holds is confirmed
rather than typed again, and a refused field still stops the flow. For
"someone I look after" the managed-profile form takes the profile's
place, because that record is created here, after the questions; an
account without a second factor can finish without it and create it
later under Settings.

Confirming posts the completion, passes the first-result step outright
when there is no task to offer, and goes where the step machine says.

messages/en.json

@@ -4719,6 +4719,27 @@
           "metric": "kg and cm",
           "imperial": "lb and ft/in"
         }
+      },
+      "confirm": {
+        "title": "Here is what your answers switch on",
+        "body": "One look, then HealthLog is set up. Nothing here is final.",
+        "modulesTitle": "Modules",
+        "switchedOn": "Switched on: {modules}.",
+        "nothingExtra": "Your answers switch on no extra module; the core readings are always there.",
+        "alwaysOn": "Always on: {modules}, and the core readings (weight, blood pressure, pulse).",
+        "everythingElse": "Everything else stays one click away under",
+        "modulesLink": "Settings, Modules",
+        "glucoseUnit": "Blood glucose",
+        "unitPreference": "Units",
+        "language": "Language",
+        "timezone": "Time zone",
+        "changeInSettings": "Change these under Settings, Account",
+        "cta": "Confirm and continue",
+        "managedTitle": "The person you look after",
+        "managedBody": "Their record has no login of its own; you look after it from your account. A second factor on your account is required to create it.",
+        "managedCreate": "Create the profile and finish",
+        "managedLater": "You can also create it later under Settings, Shared access.",
+        "finishWithoutProfile": "Finish without the profile"
       }
     }
   },