Add post-navigation hooks and browser lifecycle hooks

[vdusek]

Context

Crawlee JS provides navigation hooks and browser lifecycle hooks that Python is missing. See parity report for broader context.

Gaps

1. Post-navigation hooks (main gap)

JS BrowserCrawler and HttpCrawler both support postNavigationHooks — they run after page.goto() / HTTP request completes but before the request handler. Useful for CAPTCHA detection, response validation, etc.

Python only has only pre_navigation_hook. No post-navigation equivalent exists.

2. Browser lifecycle hooks (BrowserPool)

JS BrowserPool exposes 6 hook types, these are for consideration:

• preLaunchHooks / postLaunchHooks — before/after browser launch
• prePageCreateHooks / postPageCreateHooks — before/after new page creation
• prePageCloseHooks / postPageCloseHooks — before/after page close

Python's BrowserPool has no lifecycle hooks.

Reference

• JS BrowserCrawler hooks: packages/browser-crawler/src/internals/browser-crawler.ts
• JS BrowserPool hooks: packages/browser-pool/src/browser-pool.ts
• Python pre-nav hooks: src/crawlee/crawlers/_playwright/_playwright_crawler.py
• Python BrowserPool: src/crawlee/browsers/_browser_pool.py