Refactor: Use @simpleworkjs/conf for configuration

- Replace ENV vars with proper config system
- Add conf/ directory with base, development, production, secrets
- Add secrets.example.js template
- Update .gitignore for secrets.js
- Show environment in startup banner

conf/base.js

@@ -0,0 +1,36 @@
+/**
+ * Base configuration - shared across all environments
+ */
+
+module.exports = {
+  server: {
+    port: 3000,
+    host: '0.0.0.0'
+  },
+  
+  gateway: {
+    url: 'http://127.0.0.1:18789',
+    token: 'a41984619a5f4b9bf9148ab6eb4abca53eb796d046cbbec5'
+  },
+  
+  session: {
+    secret: 'change-me-in-production',
+    maxAge: 24 * 60 * 60 * 1000 // 24 hours
+  },
+  
+  auth: {
+    disabled: false,
+    ldap: {
+      enabled: false,
+      url: 'ldap://localhost:389',
+      baseDN: 'ou=users,dc=example,dc=com',
+      bindDN: '',
+      bindPassword: '',
+      searchFilter: '(uid={{username}})'
+    }
+  },
+  
+  data: {
+    dir: './data'
+  }
+};