[Chat] Gate group chats for under-18 users (#10548)

Co-authored-by: Eric Bailey <git@esb.lol>

src/ageAssurance/const.ts

@@ -0,0 +1,28 @@
+import {
+  ageAssuranceRuleIDs as ids,
+  type AppBskyAgeassuranceDefs,
+} from '@atproto/api'
+
+import {AgeAssuranceAccess} from '#/ageAssurance/types'
+
+/**
+ * Minimum age required to access the app at all.
+ */
+export const MIN_ACCESS_AGE = 13
+
+export const FALLBACK_REGION_CONFIG: AppBskyAgeassuranceDefs.ConfigRegion = {
+  countryCode: '*',
+  regionCode: undefined,
+  minAccessAge: MIN_ACCESS_AGE,
+  rules: [
+    {
+      $type: ids.IfDeclaredOverAge,
+      age: MIN_ACCESS_AGE,
+      access: AgeAssuranceAccess.Full,
+    },
+    {
+      $type: ids.Default,
+      access: AgeAssuranceAccess.None,
+    },
+  ],
+}