Add ESLint + Prettier + EditorConfig tooling at repo root

v1.0 Phase 1.1 — repo-wide lint/format baseline.

- eslint.config.mjs (flat config) lints server, client, shared
- .prettierrc.json, .prettierignore, .editorconfig, .nvmrc
- Root package.json holds shared devDeps; per-package scripts keep
  their typecheck + test runners
- Fix 7 lint issues surfaced by the baseline run:
  - TicketDetail.tsx: replace ternary-with-side-effects with if/else
  - admin/Users.tsx: escape apostrophe in JSX
  - errorHandler.ts: typed err as unknown with ErrorLike refinement
  - users.ts: Prisma.UserUpdateInput instead of Record<string, any>
  - seed.ts: drop unused goddard binding
- Run prettier across tracked sources for a clean formatting baseline

docker-compose.yml

@@ -15,7 +15,7 @@ services:
     volumes:
       - postgres_data:/var/lib/postgresql/data
     healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U postgres"]
+      test: ['CMD-SHELL', 'pg_isready -U postgres']
       interval: 5s
       timeout: 5s
       retries: 5
@@ -40,7 +40,7 @@ services:
     image: ${REGISTRY}/josh/ticketing-client:${TAG:-latest}
     restart: unless-stopped
     ports:
-      - "${PORT:-3080}:80"
+      - '${PORT:-3080}:80'
     depends_on:
       - server
     networks: