fix: ensure SSR always fetches fresh assets from database

Root cause: Dockerfile copied only browser/ to nginx; server/server.mjs
was built but never deployed or executed. Prerender baked DEFAULT_CONFIG
into static HTML with no API at build time, causing stale content on
every initial paint.

Changes:
- Dockerfile: serve stage uses node:22-alpine, installs nginx via apk,
  copies both browser/ and server/ bundles from build stage
- docker-entrypoint.sh: starts Angular SSR Node process on port 4200,
  waits for readiness, exports SSR_API_BASE_URL, then exec nginx
- nginx.conf.template: adds upstream ssr_backend block (127.0.0.1:4200),
  proxies / to SSR backend, static assets served directly with 1y cache
- app.server.routes.ts: all routes switched from RenderMode.Prerender
  to RenderMode.Server for zero stale content
- server.ts: removed dead prerender code (PRERENDERED_ROUTES,
  isPrerenderedRoute, allowStaticRouteRender)
- main.server.ts: injects SSR-aware apiBaseUrl via APP_CONFIG
  (reads SSR_API_BASE_URL env var)
- server.spec.ts: updated 5 test suites + added 5 new suites (31 tests)
  covering server.ts cleanup, RenderMode.Server, entrypoint lifecycle,
  Dockerfile build, nginx upstream proxy, and API URL injection
- vitest.config.ts: added server.spec.ts to include pattern

Request flow: Browser -> nginx (port 80) -> SSR server (port 4200)
-> Angular SSR -> HttpClient -> localhost:80/api/station-config
-> nginx proxies to api:8000 -> fresh data rendered in HTML

server.ts

@@ -4,44 +4,12 @@ import {
   isMainModule,
   writeResponseToNodeResponse,
 } from '@angular/ssr/node';
-import { AngularAppEngine } from '@angular/ssr';
 import * as http from 'node:http';
 
-// Enable serving prerendered static HTML from disk. Without this flag the
-// engine falls back to SSR for every route, ignoring the prerendered output.
-AngularAppEngine.ɵallowStaticRouteRender = true;
-
-/**
- * Public routes prerendered at build time (SSG — Static Site Generation).
- * These five routes are compiled to static HTML during `ng build` and
- * served directly from disk at runtime for optimal performance and SEO.
- * The list here mirrors `prerender-routes.txt` and the Prerender entries
- * in `src/app/app.server.routes.ts`.
- */
-export const PRERENDERED_ROUTES: readonly string[] = [
-  '/',
-  '/about',
-  '/schedule',
-  '/events',
-  '/contact',
-];
-
-/**
- * Normalise a request pathname and check against prerendered routes.
- * Handles both bare paths (`/about`) and trailing-slash variants (`/about/`).
- */
-export function isPrerenderedRoute(url: string): boolean {
-  const pathname = new URL(url, 'http://localhost').pathname;
-  const normalised = pathname.endsWith('/') && pathname !== '/'
-    ? pathname.slice(0, -1)
-    : pathname;
-  return PRERENDERED_ROUTES.includes(normalised);
-}
-
 /**
  * Lazily instantiate AngularNodeAppEngine so the engine boots only when
- * the first request arrives. The engine handles both prerendered route
- * lookups and on-demand SSR bootstrapping internally.
+ * the first request arrives. All routes use RenderMode.Server — every
+ * request triggers on-demand SSR that fetches fresh API data before rendering.
  */
 let appEngine: AngularNodeAppEngine | null = null;
 function getEngine(): AngularNodeAppEngine {
@@ -53,22 +21,10 @@ function getEngine(): AngularNodeAppEngine {
 
 /**
  * Handle incoming requests using the Angular SSR engine.
- *
- * Prerendered routes (/ , /about, /schedule, /events, /contact) are served
- * as pre-generated static HTML from the build output. All other routes
- * fall back to server-side rendering (SSR) or the fallback 404 handler.
+ * Every request is rendered on the server with fresh data from the API.
  */
 const requestHandler = createNodeRequestHandler(async (req, res, next) => {
   try {
-    const prerendered = isPrerenderedRoute(req.url || '/');
-    if (prerendered) {
-      console.log(`[SSR] Prerendered route: ${req.url}`);
-    }
-
-    // AngularNodeAppEngine handles manifest registration internally —
-    // no manual bootstrap import needed. For prerendered routes it
-    // returns pre-generated static HTML; for SSR routes it bootstraps
-    // the Angular app on demand.
     const response = await getEngine().handle(req);
 
     if (response) {