fix(dev): Vite-API-Proxy, Auth, Stripe-Mails und Backend-Erweiterungen

- Client: API-Basis-URL (joinApiUrl, /v1-Falle), Vite strictPort + Proxy 127.0.0.1, Nicht-JSON-Fehler

- Server: /api-404 ohne Wildcard-Bug, SPA-Fallback, Auth-Middleware, Cron, Mailer, Crypto

- Routen: OAuth-State, Email/Stripe/Analytics; client/.env.example

Made-with: Cursor

server/jobs/reset-counters.mjs

@@ -0,0 +1,39 @@
+/**
+ * Scheduled counter resets (UTC).
+ */
+
+import cron from 'node-cron'
+import { emailStats } from '../services/database.mjs'
+import { log } from '../middleware/logger.mjs'
+
+export function startCounterJobs() {
+  cron.schedule(
+    '0 0 * * *',
+    async () => {
+      const t = new Date().toISOString()
+      try {
+        const n = await emailStats.resetDaily()
+        log.info(`[cron] resetDaily at ${t} — updated ${n} email_stats documents`)
+      } catch (e) {
+        log.error('[cron] resetDaily failed', { error: e.message })
+      }
+    },
+    { timezone: 'UTC' }
+  )
+
+  cron.schedule(
+    '0 0 1 * *',
+    async () => {
+      const t = new Date().toISOString()
+      try {
+        const n = await emailStats.resetWeekly()
+        log.info(`[cron] resetWeekly at ${t} — updated ${n} email_stats documents`)
+      } catch (e) {
+        log.error('[cron] resetWeekly failed', { error: e.message })
+      }
+    },
+    { timezone: 'UTC' }
+  )
+
+  log.success('Counter cron jobs scheduled (daily 00:00 UTC, monthly week reset 1st 00:00 UTC)')
+}