feat: complete MongoDB to CouchDB migration

- Migrate Report model to CouchDB with embedded street/user data
- Migrate UserBadge model to CouchDB with badge population
- Update all remaining routes (reports, users, badges, payments) to use CouchDB
- Add CouchDB health check and graceful shutdown to server.js
- Add missing methods to couchdbService (checkConnection, findWithPagination, etc.)
- Update Kubernetes deployment manifests for CouchDB support
- Add comprehensive CouchDB setup documentation

All core functionality now uses CouchDB as primary database while maintaining
MongoDB for backward compatibility during transition period.

🤖 Generated with [AI Assistant]

Co-Authored-By: AI Assistant <noreply@ai-assistant.com>

backend/services/couchdbService.js

@@ -412,6 +412,22 @@ class CouchDBService {
     return this.isConnected;
   }
 
+  /**
+   * Check connection health
+   */
+  async checkConnection() {
+    try {
+      if (!this.connection) {
+        return false;
+      }
+      await this.connection.info();
+      return true;
+    } catch (error) {
+      console.error("CouchDB connection check failed:", error.message);
+      return false;
+    }
+  }
+
   // Generic CRUD operations
   async createDocument(doc) {
     if (!this.isConnected) await this.initialize();
@@ -498,6 +514,62 @@ class CouchDBService {
     return await this.find(query);
   }
 
+  async findDocuments(selector = {}, options = {}) {
+    const query = {
+      selector,
+      ...options
+    };
+    return await this.find(query);
+  }
+
+  async countDocuments(selector = {}) {
+    const query = {
+      selector,
+      limit: 0, // We don't need documents, just count
+    };
+    
+    try {
+      const response = await this.db.find(query);
+      return response.total_rows || 0;
+    } catch (error) {
+      console.error("Error counting documents:", error.message);
+      throw error;
+    }
+  }
+
+  async findWithPagination(selector = {}, options = {}) {
+    const { page = 1, limit = 10, sort = {} } = options;
+    const skip = (page - 1) * limit;
+
+    const query = {
+      selector,
+      limit,
+      skip,
+      sort: Object.entries(sort).map(([field, order]) => ({
+        [field]: order === -1 ? "desc" : "asc"
+      }))
+    };
+
+    try {
+      const response = await this.db.find(query);
+      const totalCount = response.total_rows || 0;
+      const totalPages = Math.ceil(totalCount / limit);
+
+      return {
+        docs: response.docs,
+        totalDocs: totalCount,
+        page,
+        limit,
+        totalPages,
+        hasNextPage: page < totalPages,
+        hasPrevPage: page > 1,
+      };
+    } catch (error) {
+      console.error("Error finding documents with pagination:", error.message);
+      throw error;
+    }
+  }
+
   // View query helper
   async view(designDoc, viewName, params = {}) {
     if (!this.isConnected) await this.initialize();