fix(gameplay): use universe-generated AI companions

Co-authored-by: multica-agent <github@multica.ai>

supabase/migrations/0010_playable_starter_parties.sql

@@ -1,5 +1,5 @@
 -- Make a newly launched campaign playable immediately: the owner receives a
--- human-controlled starter and the party receives one persistent AI companion.
+-- human-controlled starter, and only actionable members hold the round open.
 
 create or replace function public.stage_two_create_campaign(
   p_world_id uuid,
@@ -52,30 +52,6 @@ begin
     )
   );
 
-  insert into public.characters(
-    campaign_id, user_id, name, concept, controller, abilities, hp, max_hp,
-    defense, proficiency, inventory, statuses, persona
-  ) values (
-    v_campaign_id,
-    null,
-    'Echo',
-    left('A persistent AI companion shaped by the ' || v_world.genre || ' world of ' || v_world.title || ', ready to support the player without taking over their choices.', 600),
-    'ai'::public.character_controller,
-    '{"str":9,"dex":13,"con":11,"int":13,"wis":12,"cha":10}'::jsonb,
-    11,
-    11,
-    13,
-    2,
-    '["Survey kit","Emergency supplies"]'::jsonb,
-    '[]'::jsonb,
-    jsonb_build_object(
-      'voice', 'Observant, concise, and quietly curious.',
-      'motivation', 'Help the party understand this unfamiliar world.',
-      'flaw', 'Sometimes values patterns more than instinct.',
-      'bond', 'Stays beside the player when the path turns dangerous.'
-    )
-  );
-
   insert into public.rounds(campaign_id, number) values (v_campaign_id, 1);
   return v_campaign_id;
 end;
@@ -172,38 +148,6 @@ where campaign.status = 'active'
       and character.user_id = campaign.owner_id
   );
 
-insert into public.characters(
-  campaign_id, user_id, name, concept, controller, abilities, hp, max_hp,
-  defense, proficiency, inventory, statuses, persona
-)
-select
-  campaign.id,
-  null,
-  'Echo',
-  left('A persistent AI companion shaped by the ' || world.genre || ' world of ' || world.title || ', ready to support the player without taking over their choices.', 600),
-  'ai'::public.character_controller,
-  '{"str":9,"dex":13,"con":11,"int":13,"wis":12,"cha":10}'::jsonb,
-  11,
-  11,
-  13,
-  2,
-  '["Survey kit","Emergency supplies"]'::jsonb,
-  '[]'::jsonb,
-  jsonb_build_object(
-    'voice', 'Observant, concise, and quietly curious.',
-    'motivation', 'Help the party understand this unfamiliar world.',
-    'flaw', 'Sometimes values patterns more than instinct.',
-    'bond', 'Stays beside the player when the path turns dangerous.'
-  )
-from public.campaigns campaign
-join public.worlds world on world.id = campaign.world_id
-where campaign.status = 'active'
-  and not exists (
-    select 1 from public.characters character
-    where character.campaign_id = campaign.id
-      and character.controller = 'ai'::public.character_controller
-  );
-
 create or replace function public.dng_schema_version()
 returns integer language sql stable security definer set search_path = '' as $$
   select 10;