Function compute_modifiers 

pub fn compute_modifiers(
    technique: &Technique,
    differential: &DifferentialSet,
) -> ModifierResult

Computes the runtime evidence modifiers for a Contradictory outcome.

Runs three gates in parallel:

• precondition_confidence: auth/method/parser gates plus applicability markers.
• surface_relevance: detects mis-surfaced status contradictions.
• control_integrity: detects route-mutation control destruction.

Block-reason precedence when multiple gates fire: precondition > control > surface.