feat: add org admin SPA for models, roles and provider

Introduce admin-web (Skeleton/SvelteKit), Prisma models for provider connection / OrgModel / OrgRole, DB-backed runtime settings, and admin API routes so org admins can manage agent configuration end-to-end.

hub/admin-web/vite.config.ts

@@ -0,0 +1,13 @@
+import { sveltekit } from '@sveltejs/kit/vite';
+import tailwindcss from '@tailwindcss/vite';
+import { defineConfig } from 'vite';
+
+export default defineConfig({
+	plugins: [tailwindcss(), sveltekit()],
+	server: {
+		proxy: {
+			'/api': 'http://127.0.0.1:8788',
+			'/auth': 'http://127.0.0.1:8788'
+		}
+	}
+});