Rework avatars.

Now we have a concept of an avatar at the server, realm, and scene level
and we have the groundwork for a realm store. New uesrs no longer props,
they get a default avatar. New system supports gender
{male,female,neutral} and {child,adult}.

db/schema/triggers/002_user_init.sql

@@ -1,26 +0,0 @@
--- Chattyness User Initialization Trigger
--- PostgreSQL 18
---
--- Trigger to initialize new users with default props and avatar.
--- Load via: psql -f schema/triggers/002_user_init.sql
-
-\set ON_ERROR_STOP on
-
-BEGIN;
-
--- =============================================================================
--- User Registration Trigger
--- =============================================================================
--- Automatically initializes new users with default props and avatar
--- when they are inserted into auth.users.
--- =============================================================================
-
-CREATE TRIGGER trg_auth_users_initialize
-    AFTER INSERT ON auth.users
-    FOR EACH ROW
-    EXECUTE FUNCTION auth.initialize_new_user_trigger();
-
-COMMENT ON TRIGGER trg_auth_users_initialize ON auth.users IS
-    'Initialize new users with default props and avatar on registration';
-
-COMMIT;