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/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>