Create foapy.ma deprecated facade

[goruha]

Description

Convert foapy.ma to a deprecated facade that re-exports from foapy.congenerics.

Tasks

• Create foapy/ma.py as single-file module
• Import and re-export all functions from congenerics
• Add clear deprecation warnings
• Add migration guide in docstring
• Ensure backward compatibility
• Update CHANGELOG.md

Dependencies

• Requires: All congenerics modules implemented

Related to

Phase 2.1: Rename foapy.ma → foapy.congenerics

Acceptance Criteria

• Old foapy.ma API continues to work
• Deprecation warnings are clear
• Migration path is documented
• All existing tests pass