Initial commit — status checker service

Polls Nginx Proxy Manager API for proxy hosts matching configurable
domain patterns (NPM_INCLUDE_PATTERNS), HTTP-checks each every 60s,
serves results as JSON (/api/status) and a terminal-aesthetic HTML
page (/). Port 3035.

NPM connection and domain filter patterns are fully configurable via
environment variables — see README and .env.example.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.env.example

@@ -0,0 +1,7 @@
+IMAGE=registry.example.com/youruser/status:latest
+PORT=3035
+NPM_BASE_URL=http://proxy.example.com:81
+NPM_EMAIL=api@example.com
+NPM_SECRET=
+# Comma-separated regex patterns for which domains to include
+NPM_INCLUDE_PATTERNS=\.example\.com$,\.dev\.example\.com$