Add explicit nullability to replace boolean

[goldenice]

Merge #6 first

This adds explicit nullability, the ability to provide 'NULLABLE' and 'NOT NULL' instead of true and false. This makes it clearer what is going on at a glance. In the future we'll probably deprecate passing the booleans and remove it in the next major release.

[Copilot]

Pull Request Overview

This PR introduces explicit nullability options for entity field definitions, allowing developers to use 'NULLABLE' and 'NOT NULL' string literals instead of boolean values for better code readability. The change maintains backward compatibility with existing boolean values.

Key changes:

• Adds new Nullable type that accepts string literals or legacy boolean values
• Introduces isNullable() helper function to handle both old and new nullability formats
• Refactors type definitions into separate modules for better organization

Reviewed Changes

Copilot reviewed 18 out of 21 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/entities/Nullable.ts	Defines new nullability types and helper function
src/entities/BaseEntity.ts	Updates field and relation types to use new Nullable type
src/main.ts	Major refactor moving types to separate modules and updating nullability checks
src/types/*.ts	New type definition modules extracted from main.ts
src/helpers/sql.ts	Adds mergeSql function extracted from main.ts
src/relations/ormRelationGetter.ts	Extracts ORM relation getter logic into separate module
src/tools/validateSchema.ts	Updates import paths
tests/testHelpers.ts	Updates import path for relation getter function
.changeset/fair-knives-notice.md	Documents the feature addition

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[Copilot]

Pull Request Overview

Copilot reviewed 18 out of 21 changed files in this pull request and generated 1 comment.

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