feat: Allow RawSql JOIN tables (#9070)

[wakqasahmed]

Description

• Accept RawSql as the JOIN table, including in the Postgre and SQLSRV builders.
• Register a trailing subquery alias so ON conditions work with database prefixes.
• Document the new argument type and the signature change for custom builders.

The new base test failed with the original TypeError before the change. The local PHP image has no coverage driver, so coverage is left to CI.

Closes #9070.

Test plan:

• JoinTest.php (14 tests)
• PHP 8.2 syntax checks for the three changed production files
• File-scoped Rector dry run

Checklist:

• Securely signed commits
• Component(s) with PHPDoc blocks, only if necessary or adds value (without duplication)
• Unit testing, with >80% coverage (coverage measurement pending CI)
• User guide updated
• Conforms to style guide

[wakqasahmed]

The updated JOIN regressions pass locally (16 tests), and the review fix is in 9d63234. The Oracle CI job failed in the randomized AutoReview test FrameworkCodeTest::testDeprecationsAreProperlyVersioned() because app/Transformers is absent; the failure does not exercise JOIN code. GitHub denied my rerun request with 403 (upstream admin rights required). Could a maintainer rerun the failed job?

[michalsn]

I think it looks good. But please update the join signature in Model.php.

[michalsn]

Thank you. Please rebase to fix the PHPStan error.

[wakqasahmed]

Rebased onto 4.8 (same for #10574). The earlier PHPStan errors are gone. The one left is in system/Session/Handlers/RedisHandler.php (Redis::set() options expects array, int given), which neither PR touches. 4.8's own PHPStan run was green on Oct 4, so it looks like a phpredis stub change in CI since then rather than something from this branch.