feat: reuse Sessions correctly in BasicCrawler

[barjin]

Makes BasicCrawler (and its subclasses) reuse Session instances according to the sessionReuseStrategy. Before, the BasicCrawler would create a single-use Session for each Request unless instructed otherwise (e.g., via request.sessionId).

Refactors small bits around the Session lifecycle in BasicCrawler.

Closes #3595

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Depends on #3599

[Copilot]

Pull request overview

This PR changes BasicCrawler’s session lifecycle so that sessions are no longer forced into single-use, and introduces proxy assignment at session creation time to keep proxyInfo consistent with the Session instance.

Changes:

• Replace per-request single-use session creation with SessionPool.getSession() to allow session reuse.
• When proxyConfiguration is used, assign proxyInfo when creating sessions in the pool and expose it via context.
• Add a test asserting proxyInfo is present on both the Session and the handler context.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 6 comments.

File	Description
packages/basic-crawler/src/internals/basic-crawler.ts	Switch to session reuse via getSession() and introduce a custom createSessionFunction that assigns proxyInfo.
test/core/crawlers/basic_crawler.test.ts	Add coverage for proxyConfiguration producing proxyInfo on Session and in the handler context.

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[Copilot]

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.

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[l2ysho]

thx @barjin for this, after hours I spent in debugging remote browser approach, this PR makes perfect sense. I do not see any blocking issue.