Demo: PHP 8.5 pipe operator on the CI matrix

[pjeweb]

Summary

• Temporary PHPUnit test that uses the PHP 8.5 pipe operator (|>) so the new CI matrix can show red on 8.2–8.4 and green on 8.5.
• Local run on PHP 8.5.9 passed; older versions should fail at parse time when PHPUnit loads the file.
• Do not merge. This is only a matrix smoke check and can be closed after the checks come back.

Test plan

• Confirm Tests (PHP 8.2), Tests (PHP 8.3), and Tests (PHP 8.4) fail with a pipe-operator syntax error.
• Confirm Tests (PHP 8.5) is green.
• Close the PR without merging once the red/green split is visible.