// Package diff provides utilities for comparing database schemas and identifying differences.
//
// # Overview
//
// The diff package compares two database models at various granularity levels (database,
// schema, table, column) and produces detailed reports of differences including:
//   - Missing items (present in source but not in target)
//   - Extra items (present in target but not in source)
//   - Modified items (present in both but with different properties)
//
// # Usage
//
// Compare two databases and format the output:
//
//	result := diff.CompareDatabases(sourceDB, targetDB)
//	err := diff.FormatDiff(result, diff.OutputFormatText, os.Stdout)
//
// # Output Formats
//
// The package supports multiple output formats:
//   - OutputFormatText: Human-readable text format
//   - OutputFormatJSON: Structured JSON output
//   - OutputFormatYAML: Structured YAML output
//
// # Comparison Scope
//
// The comparison covers:
//   - Schemas: Name, description, and contents
//   - Tables: Name, description, and all sub-elements
//   - Columns: Type, nullability, defaults, constraints
//   - Indexes: Columns, uniqueness, type
//   - Constraints: Type, columns, references
//   - Relationships: Type, from/to tables and columns
//   - Views: Definition and columns
//   - Sequences: Start value, increment, min/max values
//
// # Use Cases
//
//   - Schema migration planning
//   - Database synchronization verification
//   - Change tracking and auditing
//   - CI/CD pipeline validation
package diff