fix: Supports proxies with authentication

[gosom]

Previous version supported only proxies without authentication due to a playwright issue.

In this version this limitation is bypassed by starting a local proxy that handles authentication.

[Copilot]

Pull Request Overview

This PR adds support for proxies with authentication by implementing a local proxy that handles authentication, bypassing a previous playwright limitation.

Key changes:

• Added a new Proxies() method to the ProxyRotator interface to retrieve proxy URLs
• Implemented a local authentication proxy system (AuthProxy and ProxyPool) that handles both HTTP and SOCKS5 proxies with credentials
• Updated existing fetchers to use the new proxy authentication system

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
services.go	Added Proxies() method to ProxyRotator interface
proxy.go	Added FullURL() method and modernized proxy validation logic
go.mod	Updated Go version and dependencies
cmd/proxy-test/main.go	Added test command for proxy authentication
adapters/proxy/proxy_test.go	Minor loop modernization
adapters/proxy/proxy.go	Implemented new Proxies() method and added debug output
adapters/fetchers/stealth/stealth.go	Updated to use new proxy authentication
adapters/fetchers/jshttp/pool.go	New proxy pool management for authentication
adapters/fetchers/jshttp/local_proxy.go	Core local proxy implementation with authentication handling
adapters/fetchers/jshttp/jshttp.go	Updated to use new proxy pool system

---

_{Tip: Customize your code reviews with copilot-instructions.md. Create the file or learn how to get started.}