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/jest.config.ts

@@ -0,0 +1,39 @@
+/** @type {import('jest/dist/types').InitialOptionsTsJest} */
+
+import type { Config } from 'jest/build/index';
+
+const config:Config = {
+  // preset: 'ts-jest',
+  transform: {
+    '^.+\\.tsx?$': [
+      'esbuild-jest', {
+        sourcemap:true, // bez ovog VS code umjesto originala prikazuje transpilirane datoteke
+        target:'es2020' // ovo je nužno kako bi BigInt funkcionirao
+      }]
+  },
+  maxWorkers: 4,
+  testEnvironment: 'node',
+  // The root directory that Jest should scan for tests and modules within
+  rootDir: "./",
+  // A list of paths to directories that Jest should use to search for files in
+  roots: [
+    "<rootDir>/tests",
+  ],
+  // The glob patterns Jest uses to detect test files
+  testMatch: [
+    "**/?(*.)+(spec).[tj]s?(x)",
+  ],
+  // Automatically clear mock calls and instances between every test
+  clearMocks: true,
+  // An array of regexp pattern strings that are matched against all source file paths, matched files will skip transformation
+  transformIgnorePatterns: ["/node_modules/"],
+  // An array of regexp pattern strings that are matched against all test paths, matched tests are skipped
+  testPathIgnorePatterns: ["/node_modules/", "/build/"],
+  // Indicates whether each individual test should be reported during the run
+  verbose: true,
+  setupFiles: [
+    'dotenv/config', // učitaj varijable iz .env i učini ih dostupne testiranom software-u
+  ]
+};
+
+module.exports = config;