feat: Add MySQL to PostgreSQL migration tool with JSONB transformation

Implement comprehensive migration solution with:
- Full and incremental migration modes
- JSONB schema transformation for RAWDATACOR and ELABDATADISP tables
- Native PostgreSQL partitioning (2014-2031)
- Optimized GIN indexes for JSONB queries
- Rich logging with progress tracking
- Complete benchmark system for MySQL vs PostgreSQL comparison
- CLI interface with multiple commands (setup, migrate, benchmark)
- Configuration management via .env file
- Error handling and retry logic
- Batch processing for performance (configurable batch size)

Database transformations:
- RAWDATACOR: 16 Val columns + units → single JSONB measurements
- ELABDATADISP: 25+ measurement fields → structured JSONB with categories

🤖 Generated with Claude Code

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -0,0 +1,15 @@
+[project]
+name = "mysql2postgres"
+version = "0.1.0"
+description = "Robust MySQL to PostgreSQL migration tool with schema transformation and performance benchmarking"
+readme = "README.md"
+requires-python = ">=3.10"
+dependencies = [
+    "pymysql>=1.1.0",
+    "psycopg[binary]>=3.1.0",
+    "python-dotenv>=1.0.0",
+    "click>=8.1.0",
+    "rich>=13.0.0",
+    "pydantic>=2.5.0",
+    "pydantic-settings>=2.1.0",
+]