Refactor config routes: explicit dependency injection

- Updated all config route modules to use destructured dependencies
- Added JSDoc comments for factory functions
- Replaced ctx. references with direct parameter access
- All files pass syntax validation

Files refactored:
- routes/config/assets.js
- routes/config/backup.js
- routes/config/settings.js
- routes/config/index.js (orchestrator)

dashcaddy-api/routes/config/index.js

@@ -1,9 +1,22 @@
 const express = require('express');
 
+/**
+ * Config routes aggregator
+ * @param {Object} ctx - Application context (for backward compatibility)
+ * @returns {express.Router}
+ */
 module.exports = function(ctx) {
   const router = express.Router();
-  router.use(require('./settings')(ctx));
-  router.use(require('./assets')(ctx));
-  router.use(require('./backup')(ctx));
+  
+  const deps = {
+    configStateManager: ctx.configStateManager,
+    servicesStateManager: ctx.servicesStateManager,
+    asyncHandler: ctx.asyncHandler,
+    log: ctx.log
+  };
+  
+  router.use(require('./settings')(deps));
+  router.use(require('./assets')(deps));
+  router.use(require('./backup')(deps));
   return router;
 };