[fix](function) Support bracketed IPv6 in parse_url

[Mryange]

Problem Summary: parse_url treated colons inside bracketed IPv6 literals as port separators, producing incorrect HOST and PORT results. The FE constant-folding and BE execution paths now recognize the closing bracket as the host boundary and only parse a port after ]:.

Release note

Support extracting HOST and PORT from URLs containing bracketed IPv6 literals.

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
• Add branch pick label

[hello-stephen]

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1. What problem was fixed (it's best to include specific error reporting information). How it was fixed.
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