feat: complete pre-launch audit — frontend polish, churn prevention, login history, financial reports, configurable checkout

Includes all work from phases 6-9+ and frontend polish rounds 1 & 2:

- Login history with device trust, new device notifications, session management
- Churn prevention: cancellation surveys, winback campaigns with email sequences
- Financial reports: revenue, P&L, tax, aging, refund, subscription reports with PDF/CSV/JSON export
- Configurable checkout: plan config groups/options, build-your-own VPS
- Frontend polish: fix broken legal links, add SEO meta tags, favicon, font display=swap,
  Head titles on all 14 marketing pages, mobile responsive fixes, AuthLayout legal footer,
  remove false 24/7 claims, hide empty stats, correct uptime SLA to 99.9%,
  GameServers notify buttons linked to /contact, 301 redirects for /terms and /privacy
- WHMCS migration scripts
- Update legal page effective dates to March 16, 2026

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

scripts/whmcs-migrate/plan_mapping.json

@@ -0,0 +1,46 @@
+{
+    "_comment": "WHMCS product ID → EZSCALE plan slug. Products not listed here will be SKIPPED (not auto-created).",
+    "mappings": {
+        "194": "vps-1",
+        "195": "vps-2",
+        "230": "vps-4",
+        "196": "vps-4",
+        "231": "stor-500",
+        "197": "vps-8",
+        "232": "vps-16",
+        "198": "vps-16",
+        "199": "vps-32",
+        "161": "vps-3-custom",
+        "201": "dell-r330-lff",
+        "117": "dell-r420-lff",
+        "110": "dell-r620-sff-10-bay",
+        "143": "dell-r620-sff-8-bay",
+        "125": "dell-r520-lff",
+        "104": "dell-r430-lff",
+        "209": "dell-r630-sff",
+        "109": "dell-r730-lff",
+        "203": "stor-36bay",
+        "70": "hosting-small",
+        "96": "hosting-medium",
+        "97": "hosting-large",
+        "106": "hosting-dedicated",
+        "12": "mysql-bronze",
+        "13": "mysql-silver",
+        "14": "mysql-gold",
+        "15": "mysql-platinum",
+        "1": "procon-layer",
+        "170": "veeam-enterprise-plus",
+        "171": "veeam-standard",
+        "172": "veeam-cloud-connect"
+    },
+    "skip": [
+        "3",
+        "37",
+        "62",
+        "147", "148", "149", "150", "151", "152", "153", "154", "155", "156", "157",
+        "173", "174", "175", "176", "177", "178", "179",
+        "180", "159", "111",
+        "213",
+        "224", "225", "226", "227", "228", "229"
+    ]
+}