v2.2: Verkaufsfertig-Fundament — Mollie/Payment-Abstraktion, MwSt/Grundpreis (PAngV), Versandzonen, Bestellmails (Listmonk/SMTP/Log), Feature-Flags

- payments.js: einheitliche createPayment/Webhook-Schnittstelle (Mollie Default, Stripe, Demo); Auto-Provider-Wahl; Mollie-REST + /api/payments/webhook (idempotent); Fake-Key => sauberer Demo-Fallback
- mailer.js: sendMail via Listmonk-Tx / SMTP (nodemailer) / Log-Fallback (email_log); gebrandete Bestellbestaetigung bei paid
- DACH: products.mwst + base_amount/base_unit/base_price_per (Grundpreis); Storefront/Warenkorb/Checkout/Erfolg/Admin mit MwSt-Ausweis + Versand-Transparenz; tax_cents/shipping_cents/country an Orders
- shipping_zones-Tabelle + CRUD + shippingFor(); Admin 'Versand'; serverseitige Versandberechnung in /api/checkout + /api/shipping-quote (Laenderwahl live)
- Feature-Flags (feature_*) + feature()-Helper; Admin Module-Toggles; Newsletter-Gating (Popup/Subscribe)
- Admin-API/Manifest/ai-admin.txt um shipping_zones erweitert; MCP list/upsert/delete_shipping; README/.env.example ergaenzt; Version 2.2.0

package-lock.json

@@ -13,6 +13,7 @@
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         "astro": "^5.6.0",
         "better-sqlite3": "^11.8.1",
+        "nodemailer": "^6.10.1",
         "stripe": "^17.5.0"
       }
     },
@@ -4178,6 +4179,15 @@
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       "license": "MIT"
     },
+    "node_modules/nodemailer": {
+      "version": "6.10.1",
+      "resolved": "https://registry.npmjs.org/nodemailer/-/nodemailer-6.10.1.tgz",
+      "integrity": "sha512-Z+iLaBGVaSjbIzQ4pX6XV41HrooLsQ10ZWPUehGmuantvzWoDVBnmsdUcOIDM1t+yPor5pDhVlDESgOMEGxhHA==",
+      "license": "MIT-0",
+      "engines": {
+        "node": ">=6.0.0"
+      }
+    },
     "node_modules/normalize-path": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/normalize-path/-/normalize-path-3.0.0.tgz",