feat: age verification with an ID document (Didit), and closed registration (#4)

## Age verification with Didit

A new provider (`apps/api/src/age/didit.ts`) behind the existing vendor-neutral age interface. A person verifies once with an ID document, a passive liveness check and a face match; after that, all their linked IMVU accounts count as adult. The hub keeps only "over 18": never the document, photo or birth date.

- Webhooks are checked against Didit's signatures (the raw body or V2, with `-Previous` during secret rotation), and old ones are rejected. If the webhook has no decision, the hub fetches it from Didit.
- A later answer replaces an earlier one. An approval that's taken back (say, after a manual review) becomes `revoked`. A check still in review stays pending.
- Limits, for every provider: one unfinished check per person (starting again resumes it), at most 3 checks in 30 days, none once verified, and a monthly cap (`DIDIT_MONTHLY_LIMIT`, default 30: since 2026-11-01, Didit's free plan is $10 of credit a month, and a check costs $0.30).
- People are only ever sent back to the hub's website.
- The Account page gets an Age Verification card.
- Configuration: `AGE_PROVIDERS=imvu,didit`, `DIDIT_API_KEY`, `DIDIT_WORKFLOW_ID`, `DIDIT_WEBHOOK_SECRET`. The webhook is `<API_URL>/api/v1/age/webhook/didit`.

## Closed registration

Registration is open or closed. It's an admin's setting in the console, with its default from `REGISTRATION`.

- When it's closed, new accounts can only sign in until a moderator approves them, or declines them (which deletes the account).
- The website shows people who are waiting a waiting page, and the API treats them as signed out everywhere but `/me`.
- The console gets a Waiting count, a Waiting for approval filter, Approve and Decline on a person's page, and a Registration setting.
- The migration adds `user.approved` (existing accounts stay approved) and `hub_setting`.

## Testing

- New tests cover Didit (with a fake Didit server), the limits, revocation, return addresses and registration.
- `bun run test`: 35 pass. `bun run check-types` passes.
- Checked locally: the account, waiting, sign-up and console pages render.
- Not run against Didit itself yet. The sandbox workflow "T5DE Age Check" is published, and the next step is a real webhook once this is on staging.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

## Age verification with Didit

A new provider (`apps/api/src/age/didit.ts`) behind the existing vendor-neutral age interface. A person verifies once with an ID document, a passive liveness check and a face match; after that, all their linked IMVU accounts count as adult. The hub keeps only "over 18": never the document, photo or birth date.

- Webhooks are checked against Didit's signatures (the raw body or V2, with `-Previous` during secret rotation), and old ones are rejected. If the webhook has no decision, the hub fetches it from Didit.
- A later answer replaces an earlier one. An approval that's taken back (say, after a manual review) becomes `revoked`. A check still in review stays pending.
- Limits, for every provider: one unfinished check per person (starting again resumes it), at most 3 checks in 30 days, none once verified, and a monthly cap (`DIDIT_MONTHLY_LIMIT`, default 30: since 2026-11-01, Didit's free plan is $10 of credit a month, and a check costs $0.30).
- People are only ever sent back to the hub's website.
- The Account page gets an Age Verification card.
- Configuration: `AGE_PROVIDERS=imvu,didit`, `DIDIT_API_KEY`, `DIDIT_WORKFLOW_ID`, `DIDIT_WEBHOOK_SECRET`. The webhook is `<API_URL>/api/v1/age/webhook/didit`.

## Closed registration

Registration is open or closed. It's an admin's setting in the console, with its default from `REGISTRATION`.

- When it's closed, new accounts can only sign in until a moderator approves them, or declines them (which deletes the account).
- The website shows people who are waiting a waiting page, and the API treats them as signed out everywhere but `/me`.
- The console gets a Waiting count, a Waiting for approval filter, Approve and Decline on a person's page, and a Registration setting.
- The migration adds `user.approved` (existing accounts stay approved) and `hub_setting`.

## Testing

- New tests cover Didit (with a fake Didit server), the limits, revocation, return addresses and registration.
- `bun run test`: 35 pass. `bun run check-types` passes.
- Checked locally: the account, waiting, sign-up and console pages render.
- Not run against Didit itself yet. The sandbox workflow "T5DE Age Check" is published, and the next step is a real webhook once this is on staging.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-authored-by: dhkatz <[email protected]>

apps/web/app/account/actions.ts

@@ -1,5 +1,6 @@
 "use server";
 import { revalidatePath } from "next/cache";
+import { redirect } from "next/navigation";
 import { api, unwrap } from "@/lib/api";
 import { attempt, field, type ActionState } from "@/lib/actions";
 
@@ -58,3 +59,15 @@ export async function signOutComputers(_: ActionState, _form: FormData): Promise
     return "Signed out everywhere.";
   });
 }
+
+/** Starts an age check with a provider that checks the person, and sends them to its page. */
+export async function startAgeCheck(_: ActionState, form: FormData): Promise<ActionState> {
+  let url: string | undefined;
+  const state = await attempt(async () => {
+    const started = unwrap(await api.age({ provider: field(form, "provider") }).start.post({ returnURL: "/account?age=back" }));
+    if (started.kind === "redirect") url = started.url;
+    done();
+  });
+  if (url) redirect(url);
+  return state;
+}

apps/web/app/account/age-card.tsx

@@ -0,0 +1,68 @@
+import { ActionForm, SubmitButton } from "@/components/forms";
+import { Tag } from "@/components/status";
+import { TimeAgo } from "@/components/time";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+import type { AgeInfo } from "@/lib/api";
+import { startAgeCheck } from "./actions";
+
+/** The person's own age check (an ID document, say), which covers all their IMVU accounts. */
+export function AgeCard({ age, back }: { age: AgeInfo; back: boolean }) {
+  const ways = age.providers.filter((p) => p.scope === "person");
+  if (ways.length === 0) return null;
+  const now = Date.now();
+  const verified = age.checks.find(
+    (c) => c.status === "complete" && c.overEighteen && (!c.expiresAt || new Date(c.expiresAt).getTime() > now),
+  );
+  const latest = age.checks[0];
+  const pending = latest?.status === "pending" ? latest : undefined;
+  const vendorOf = (id: string) => age.providers.find((p) => p.id === id)?.vendor ?? id;
+
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle>Age Verification</CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-4 text-sm">
+        {verified ? (
+          <p className="flex flex-wrap items-center gap-2">
+            <Tag tone="adult">Age verified</Tag>
+            <span className="text-muted-foreground">
+              with {vendorOf(verified.provider)} <TimeAgo iso={verified.checkedAt ?? verified.createdAt} />. All your
+              IMVU accounts count as adult.
+            </span>
+          </p>
+        ) : (
+          <>
+            {pending ? (
+              <p>
+                {back
+                  ? "Thanks. Your check is being processed; this page shows the result when it's done."
+                  : "Your check isn't finished yet."}
+              </p>
+            ) : latest?.status === "complete" && !latest.overEighteen ? (
+              <p>Your last check found you're under 18.</p>
+            ) : latest?.status === "failed" || latest?.status === "revoked" ? (
+              <p>Your last check didn&apos;t pass. You can try again.</p>
+            ) : (
+              <p className="text-muted-foreground">
+                Verify your age once to count as adult on all your IMVU accounts, not only those IMVU has age verified.
+              </p>
+            )}
+            {ways.map((p) => (
+              <ActionForm key={p.id} action={startAgeCheck} fields={{ provider: p.id }}>
+                <div className="space-y-2">
+                  <SubmitButton variant={pending && pending.provider !== p.id ? "outline" : "default"} pendingLabel="Starting…">
+                    {pending?.provider === p.id ? "Continue check" : `Verify with ${p.label}`}
+                  </SubmitButton>
+                  <p className="text-xs text-muted-foreground">
+                    Done by {p.vendor}. T5DE only keeps whether you&apos;re over 18, never your ID, photo or birth date.
+                  </p>
+                </div>
+              </ActionForm>
+            ))}
+          </>
+        )}
+      </CardContent>
+    </Card>
+  );
+}

apps/web/app/account/page.tsx

@@ -8,17 +8,19 @@ import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/com
 import { Input } from "@/components/ui/input";
 import { api, getMe, isModerator, unwrap } from "@/lib/api";
 import { linkAccount, signOutComputers } from "./actions";
+import { AgeCard } from "./age-card";
 import { ChallengeCard } from "./challenge-card";
 import { LinkCard } from "./link-card";
 
 export const metadata: Metadata = { title: "Account" };
 
-export default async function Account({ searchParams }: { searchParams: Promise<{ welcome?: string }> }) {
+export default async function Account({ searchParams }: { searchParams: Promise<{ welcome?: string; age?: string }> }) {
   const me = await getMe();
   if (!me) redirect("/signin?next=/account");
-  const account = unwrap(await api.account.get());
+  const [account, age] = await Promise.all([api.account.get().then(unwrap), api.age.get().then(unwrap)]);
   const { person, links, challenges, computers } = account;
-  const welcome = (await searchParams).welcome !== undefined;
+  const params = await searchParams;
+  const welcome = params.welcome !== undefined;
 
   return (
     <div className="space-y-6">
@@ -78,12 +80,14 @@ export default async function Account({ searchParams }: { searchParams: Promise<
             </p>
           )}
           <p className="text-sm text-muted-foreground">
-            Other people can&apos;t see which IMVU accounts are yours. Age-verified IMVU accounts (or with Access Pass)
-            can see adult community products; each account is checked on its own.
+            Other people can&apos;t see which IMVU accounts are yours. Adult IMVU accounts can see adult community
+            products: those IMVU has age verified (or with Access Pass), or all of them once you verify your age below.
           </p>
         </CardContent>
       </Card>
 
+      <AgeCard age={age} back={params.age === "back"} />
+
       <Card>
         <CardHeader>
           <CardTitle>T5DE on your computers</CardTitle>