Merge SERVICE role into AGENT

Every AGENT now gets an auto-generated API key on creation, shown once
in a modal. AGENTs log in with password and authenticate to the API
with X-Api-Key. pre-push.sql defensively migrates any residual SERVICE
rows to AGENT before Prisma rewrites the enum. Goddard is no longer
baked into the seed — create agents via Admin → Users.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

client/src/pages/Tickets.tsx

@@ -214,7 +214,7 @@ export default function Tickets() {
     setSearchInput(String(filters.search ?? ''));
   };
 
-  const agentUsers = users.filter((u) => u.role !== 'SERVICE');
+  const agentUsers = users;
 
   // Keyboard navigation
   useEffect(() => {