feat: add email-server-worker with clean template architecture

Add new email-server-worker project implementing a self-scheduling background worker pattern with HTTP monitoring. Removed all business-specific code from copied source, creating a clean, reusable template.

Key features:
- Self-scheduling worker loop with configurable interval
- Graceful shutdown support (Docker-compatible)
- Prometheus metrics collection
- Health check endpoints (/healthcheck, /metrics, /ping)
- Example worker template for easy customization
- Comprehensive architecture documentation in CLAUDE.md

The worker is now ready for email server implementation with no external dependencies on Evolution/MSSQL/ElasticSearch.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

email-server-worker/tests/helpers/mockHttpContext.ts

@@ -0,0 +1,33 @@
+import { Request, Response, NextFunction } from 'express';
+import { NgitLocals } from "../../src/types/NgitLocals";
+
+interface IMockHttpContext {
+  reqPath?:string
+  headersSent?:boolean
+  writableEnded?:boolean
+  method?:string
+}
+
+export const mockHttpContext = ({reqPath="/", headersSent=false, writableEnded=false, method="GET"}:IMockHttpContext|undefined = {}) => {
+    const req = {
+      path:reqPath,
+      method,
+      url:`https://localhost${reqPath}`,
+      params: {},
+    } as unknown as Request;
+  
+    const res = {
+      end: jest.fn(),
+      status: jest.fn(),
+      setHeader: jest.fn(),
+      locals: {
+        stopPrometheusTimer: jest.fn(),
+      } as unknown as NgitLocals,
+      headersSent,
+      writableEnded,
+    } as unknown as Response;
+
+    const next:NextFunction = jest.fn();
+  
+    return({req,res,next})
+  }