[EDM] Add New Templates with Decorators

[ThuF]

Description

We should introduce a new set of EDM templates that leverage the recently introduced decorators functionality in Dirigible.

Context

With the new decorators feature now available in Dirigible, we have an opportunity to enhance the EDM (Entity/Data Model) templates to take advantage of this capability.

Reference: https://www.dirigible.io/blogs/2025/12/04/dirigible-decorators/

What Needs to Be Done

• Review the existing EDM templates.
• Identify patterns where decorators can improve or simplify template logic.
• Create updated versions of those templates utilizing decorators.
• Ensure generated artifacts remain backward compatible (or document breaking changes clearly).
• Add tests/examples demonstrating usage of the new templates with decorators.
• Update documentation to reflect the introduction of decorator-based templates.

Acceptance Criteria

• New templates that use decorators exist in the EDM template collection.
• Templates generate valid and correct artifacts when decorators are applied.
• Test cases (automated/manual) validate decorated template behavior.
• Documentation is updated with examples and usage guidelines.