Implement congeneric-specific optimizations

[goruha]

Description

Implement optimized versions of core functions for congeneric (single-alphabet) sequences.

Tasks

• Implement congeneric alphabet operations
• Implement congeneric order operations
• Implement optimized interval chain generation
• Implement optimized interval tuple operations
• Implement optimized distribution calculations
• Add performance benchmarks comparing to core
• Document performance improvements

Dependencies

• Requires: Create foapy.congenerics package structure

Related to

Phase 2.1: Rename foapy.ma → foapy.congenerics

Acceptance Criteria

• All core functionality has congeneric equivalent
• Performance tests show improvement over generic core
• Code is well-documented with examples