Enforce consistent splitting of multiline boolean conditions #58

The owner requested one boolean condition part per line when a condition is multiline, rather than several || operators on one line and another on the next. PR #55 exposed the gap in StandardsServiceProvider.php; its whitespace correction is separate from enforcing this policy.

Reproduced with the exact #55 d1ecaea fixture: the current ECS 13.3.8 preset returns exit 0 and leaves the mixed layout unchanged. The manually split layout also returns 0 and is stable across two fix passes. OperatorLinebreakFixer controls placement beside existing newlines; it does not split every operator. Adding bundled PEAR MultiLineConditionSniff still accepts the mixed layout and imposes another convention, so it is not an appropriate fix. This is not a demonstrated PER-specification violation.

Investigate a bounded maintained-rule solution before introducing owned token logic or new dependencies. Published Slevomat 8.31.2 exposes alwaysSplitAllConditionParts, but source inspection shows a line-count heuristic that may miss expressions with multiline calls; it is not installed or qualified as a solution in this project.

Acceptance: define and document the intended conditional-expression scope; exact negative/positive fixtures; nested expressions, comments, multiline calls and &&/|| combinations; no unintended change to single-line conditions or short-circuit semantics; check must detect violations without mutation, fix must be safe and idempotent. Qualify the effective preset and whole-project checks. Do not claim enforcement from correcting only #55's source.