Fase 0: scaffold monorepo, SvelteKit skeleton, and dev infrastructure

- Turborepo + pnpm workspaces with apps/web and packages/types
- SvelteKit app: Tailwind, Paraglide i18n (en/es), keycloak-js, Supabase client,
  auth/collective stores, PWA service worker skeleton, all route placeholders
- packages/types: domain types (User, Collective, ShoppingList, etc.) and
  database.ts placeholder for generated types
- Justfile with dev, db-*, kc-*, build, backup, restore, deploy recipes
- infra/docker-compose.dev.yml: Postgres 15, GoTrue, PostgREST, Realtime v2.83,
  Storage, Kong (port 8001), Studio, Keycloak 24
- infra/docker-compose.prod.yml, kong.yml, db-init scripts, backup/deploy scripts
- keycloak/realm-export.json with colectivo realm and 5 dev test users
- supabase/config.toml and seed.sql with sample collective and items
- GitHub Actions: ci.yml (lint+typecheck+build) and deploy.yml (GHCR + SSH)
- .env.example documenting all required variables
- Fixed docker-compose issues: Studio image tag, Kong port conflict (8001),
  internal role passwords init script, Realtime METRICS_JWT_SECRET/APP_NAME

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/web/src/lib/auth.ts

@@ -0,0 +1,78 @@
+import Keycloak from 'keycloak-js';
+import { browser } from '$app/environment';
+import { PUBLIC_KEYCLOAK_URL, PUBLIC_KEYCLOAK_REALM, PUBLIC_KEYCLOAK_CLIENT_ID } from '$env/static/public';
+
+export interface KeycloakUser {
+	id: string;
+	email: string;
+	displayName: string;
+	preferredUsername: string;
+}
+
+let keycloak: Keycloak | null = null;
+
+export function getKeycloak(): Keycloak {
+	if (!keycloak) {
+		keycloak = new Keycloak({
+			url: PUBLIC_KEYCLOAK_URL,
+			realm: PUBLIC_KEYCLOAK_REALM,
+			clientId: PUBLIC_KEYCLOAK_CLIENT_ID
+		});
+	}
+	return keycloak;
+}
+
+export async function initAuth(): Promise<boolean> {
+	if (!browser) return false;
+
+	const kc = getKeycloak();
+
+	const authenticated = await kc.init({
+		onLoad: 'check-sso',
+		silentCheckSsoRedirectUri: `${window.location.origin}/silent-check-sso.html`,
+		// Safari blocks third-party cookies in iframes — must be false
+		checkLoginIframe: false,
+		pkceMethod: 'S256'
+	});
+
+	if (authenticated) {
+		// Schedule proactive token refresh (60s before expiry)
+		scheduleTokenRefresh(kc);
+	}
+
+	return authenticated;
+}
+
+function scheduleTokenRefresh(kc: Keycloak): void {
+	setInterval(
+		async () => {
+			try {
+				await kc.updateToken(60);
+			} catch {
+				// Token refresh failed — redirect to login
+				kc.login();
+			}
+		},
+		30 * 1000 // check every 30s
+	);
+}
+
+export function getUser(kc: Keycloak): KeycloakUser | null {
+	if (!kc.authenticated || !kc.tokenParsed) return null;
+
+	const token = kc.tokenParsed as Record<string, unknown>;
+	return {
+		id: token['sub'] as string,
+		email: token['email'] as string,
+		displayName: (token['name'] as string) ?? (token['preferred_username'] as string),
+		preferredUsername: token['preferred_username'] as string
+	};
+}
+
+export async function login(): Promise<void> {
+	getKeycloak().login();
+}
+
+export async function logout(): Promise<void> {
+	getKeycloak().logout({ redirectUri: window.location.origin });
+}