Fix flaky ci for orphan tx

[chenyukang]

What problem does this PR solve?

Problem Summary:

https://github.com/nervosnetwork/ckb/actions/runs/25428008652/attempts/1
is not stable on Windows

What is changed and how it works?

• Increase tx-pool orphan count wait timeout in orphan integration tests.
• Add clearer timeout diagnostics with actual tx-pool counts and verify queue size.
• Add a unit test covering multiple orphan transactions spending the same unknown input.

What's Changed:

Related changes

• PR to update owner/repo:
• Need to cherry-pick to the release branch

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Side effects

• Performance regression
• Breaking backward compatibility