Implement lazy loading for middleware dependencies

[jkyberneees]

No description provided.

[Copilot]

Pull Request Overview

This pull request implements lazy loading for middleware dependencies to improve startup performance and reduce the initial bundle size. Key changes include:

• Introducing lazy‐loading functions (loadPromClient, loadPino, loadJose) in middleware files.
• Adding unit tests and a standalone test script to verify lazy loading behavior.
• Updating dependency instructions and documentation in package.json and README files.

Reviewed Changes

Copilot reviewed 8 out of 8 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
test/unit/prometheus.test.js	Added tests for error handling and edge cases for Prometheus.
test-lazy-loading.js	Introduced a script to verify that middleware dependencies load lazily.
package.json	Modified dependency order to mark certain packages as optional.
lib/middleware/prometheus.js	Implemented lazy loading for prom-client and updated exports.
lib/middleware/logger.js	Implemented lazy loading for pino in the logger middleware.
lib/middleware/jwt-auth.js	Implemented lazy loading for jose in JWT authentication middleware.
lib/middleware/README.md	Updated documentation to reflect optional dependencies.
README.md	Added notes regarding optional middleware dependencies.

Comments suppressed due to low confidence (2)

test/unit/prometheus.test.js:482

• The test simulates error handling for prom-client loading but does not actually force a loading error. Consider using a mocking technique to simulate require failure so that the error path in loadPromClient() can be fully verified.

it('should handle prom-client loading error', () => {

lib/middleware/jwt-auth.js:319

• Multiple calls to loadJose() in the error handling block may add redundant overhead. Consider caching the result of loadJose() within the function scope to avoid repeated lookups during error processing.

  } else if (error instanceof errors.JWTExpired) {