fix(routes): restore ctx access in 15 route files broken by Phase 2.1 refactor

The modular refactor changed function signatures to destructured deps but
left internal ctx.* references intact, causing "ctx is not defined" errors
on /api/config, /api/logo, and many other endpoints. Also implements
loadTotpConfig and saveTotpConfig which were left as stubs.

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

dashcaddy-api/routes/config/settings.js

@@ -3,15 +3,13 @@ const { validateConfig } = require('../../config-schema');
 const { exists } = require('../../fs-helpers');
 const { ValidationError } = require('../../errors');
 
-module.exports = function({ configStateManager, asyncHandler, log }) {
 /**
  * Config settings routes factory
- * @param {Object} deps - Explicit dependencies
- * @param {Object} deps.configStateManager - Config state manager
- * @param {Function} deps.asyncHandler - Async route handler wrapper
- * @param {Object} deps.log - Logger instance
+ * @param {Object} ctx - Application context
  * @returns {express.Router}
  */
+module.exports = function(ctx) {
+  const { configStateManager, asyncHandler, log } = ctx;
   const express = require('express');
   const router = express.Router();