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

Age: a Didit provider behind the vendor-neutral age interface. A person
verifies once (ID document, passive liveness, face match) and all their
linked IMVU accounts count as adult. Webhooks are checked against Didit's
signatures; only "over 18" is kept. A later answer replaces an earlier one
(an approval taken back is revoked). Checks are limited: one unfinished
check per person, 3 in 30 days, none once verified, and a monthly cap
(DIDIT_MONTHLY_LIMIT, default 30: Didit's free plan is $10 of credit a
month and a check costs $0.30). The Account page gets an Age Verification
card.

Registration: open or closed, an admin's setting in the console
(default from REGISTRATION). Closed: new accounts can only sign in until
a moderator approves them (or declines, deleting the account); the
website shows them a waiting page and the API treats them as signed out.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

packages/db/drizzle/0009_registration.sql

@@ -0,0 +1,7 @@
+CREATE TABLE "hub_setting" (
+	"key" text PRIMARY KEY NOT NULL,
+	"value" text NOT NULL,
+	"updated_at" timestamp with time zone DEFAULT now() NOT NULL
+);
+--> statement-breakpoint
+ALTER TABLE "user" ADD COLUMN "approved" boolean DEFAULT true NOT NULL;

packages/db/drizzle/meta/_journal.json

@@ -64,6 +64,13 @@
       "when": 1793372872749,
       "tag": "0008_product_deletion",
       "breakpoints": true
+    },
+    {
+      "idx": 9,
+      "version": "7",
+      "when": 1793707706030,
+      "tag": "0009_registration",
+      "breakpoints": true
     }
   ]
 }

packages/db/src/schema.ts

@@ -43,6 +43,8 @@ export const user = pgTable(
     banExpires: timestamp("ban_expires", { withTimezone: true }),
     // How many IMVU accounts the person may link; moderators raise it on request.
     linkCap: integer("link_cap").notNull().default(10),
+    // False while a new account waits for a moderator's approval (registration closed); it can only sign in.
+    approved: boolean("approved").notNull().default(true),
   },
   (t) => [uniqueIndex("user_username_lower").on(sql`lower(${t.username})`)],
 );
@@ -473,3 +475,10 @@ export const roomDecoration = pgTable(
   },
   (t) => [index("room_decoration_owner").on(t.ownerImvuId)],
 );
+
+// The hub's settings that admins change from the console (e.g. registration: "open" or "closed").
+export const hubSetting = pgTable("hub_setting", {
+  key: text("key").primaryKey(),
+  value: text("value").notNull(),
+  updatedAt: updatedAt(),
+});