MetricsThresholds class

Metrics thresholds for violation detection.

Defines acceptable ranges for code quality metrics. Functions that exceed these thresholds are flagged as violations (hotspots).

Example:

final aggregator = MetricsAggregator(
  thresholds: MetricsThresholds(
    minMaintainability: 60.0,  // Stricter than default
    maxCyclomatic: 15,
    maxCognitive: 10,
    maxLinesOfCode: 50,
  ),
);