Add SqlScriptRunner class that implements IScriptRunner for executing
SQL scripts against the LotFinderDB cache database. Includes constructor
validation and configurable timeout support (default 1 hour).
Add the four core interfaces for the ETL pipeline:
- IImportSource: defines data sources for reading
- IDataTransformer: defines data transformation layer
- IImportDestination: defines data write destinations
- IScriptRunner: defines script execution capability
Move configuration options from Core/DataAccess/DataSync/ExcelIO to
dedicated Options folders within each project for better organization.
Update all references and tests accordingly.
Set up repository with legacy .NET Framework 4.8 source (OLD/),
new .NET 10 Blazor solution (NEW/), OpenSpec specifications,
documentation, and project configuration.