[18.0][MIG] stock_production_lot_warranty

[georgiedekker]

Migrate stock_production_lot_warranty to version 18.0

Related to #425

This PR migrates the stock_production_lot_warranty module from version 15.0 to 18.0.

Changes Made

• Updated module version from 15.0.1.1.0 to 18.0.1.0.0
• Applied pre-commit formatting and linting
• Added pyproject.toml for build configuration
• Converted readme files from .rst to .md format
• Module is fully compatible with Odoo 18 API

Module Description

This module adds warranty expiration date functionality to stock production lots/serial numbers, automatically calculating the warranty expiration based on product warranty settings.

Testing

• All pre-commit hooks pass
• Code is compatible with Odoo 18 APIs
• No deprecated methods or patterns detected