Fork xmrcheckout for Wownero (WOW)

Minimal changes from upstream xmrcheckout to support Wownero:
- Rate provider: Nonlogs WOW-BTC via Kraken BTC/USD
- Subaddress derivation: Wownero network byte overrides (53/63/54)
- Payment URI scheme: wownero:
- Dockerfile: Wownero binaries from Codeberg
- Display text: Monero→Wownero, XMR→WOW throughout UI
- Default daemon: 192.168.88.235:34568
- Added wownero-logo.svg

File and folder structure kept identical to upstream for easy sync.

nginx/conf.d/default.conf

@@ -0,0 +1,46 @@
+limit_req_zone $binary_remote_addr zone=global_rate_limit:10m rate=50r/s;
+
+server {
+  listen 80;
+  server_name wowcheckout.such.software localhost;
+
+  limit_req zone=global_rate_limit burst=200 nodelay;
+
+  if ($request_uri ~* "//+") {
+    return 308 $scheme://$host$uri$is_args$args;
+  }
+
+  location /api/ {
+    proxy_pass http://api:8000/api/;
+    proxy_http_version 1.1;
+    proxy_set_header Host $host;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+  }
+
+  location /api {
+    return 301 /api/;
+  }
+
+  location = /openapi.json {
+    proxy_pass http://api:8000/openapi.json;
+    proxy_http_version 1.1;
+    proxy_set_header Host $host;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+  }
+
+  location /qr/ {
+    alias /qr/;
+    add_header Cache-Control "public, max-age=31536000, immutable";
+    try_files $uri =404;
+  }
+
+  location / {
+    proxy_pass http://ui:3000/;
+    proxy_http_version 1.1;
+    proxy_set_header Host $host;
+    proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+    proxy_set_header X-Forwarded-Proto $scheme;
+  }
+}