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>

shared/schemas/enums.ts

@@ -1,6 +1,6 @@
 import { z } from 'zod';
 
-export const ROLES = ['ADMIN', 'AGENT', 'USER', 'SERVICE'] as const;
+export const ROLES = ['ADMIN', 'AGENT', 'USER'] as const;
 export const TICKET_STATUSES = ['OPEN', 'IN_PROGRESS', 'RESOLVED', 'CLOSED'] as const;
 
 export const roleSchema = z.enum(ROLES);