Add Windows-safe load-data script to handle CRLF line endings

[aashrayjain]

Background / Problem:
On Windows, importing OpenFlights data using load-data.sql can fail with:

ERROR 1406 (Data too long for column 'active')

This happens because Windows files use CRLF line endings (\r\n), while the original script uses LINES TERMINATED BY '\n'.
MariaDB reads the carriage return (\r) as part of the last column, causing data length errors for some short columns (like active in airlines).

Proposed Solution:

• Added a new script sql/load-data-windows.sql specifically for Windows users.
• Updated all LOAD DATA commands to use LINES TERMINATED BY '\r\n'.
• Original load-data.sql remains unchanged for Linux/macOS users.
• Updated README to include instructions for Windows users about the new script.

Recommendation / Request:

• Windows users can run load-data-windows.sql to successfully import the data.
• Maintainers may review and choose to merge, modify, or discard this PR as they see fit. This is intended as a suggestion to help Windows users and does not change the original workflow.