Feature/comprehensive testing

[y-aithnini]

Summary

• What does this PR change?

Why

• Why is this change needed?

Checklist

• Added/updated tests (if behavior changed)
• npm run lint passes
• npm run typecheck passes
• npm test passes
• npm run build passes
• Added a changeset (npx changeset) if this affects consumers

Notes

• Anything reviewers should pay attention to?

[sonarqubecloud]

Quality Gate passed

Issues
8 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[Copilot]

Pull request overview

This PR focuses on making the library more robust and publishable by adding a comprehensive Jest test suite (unit + integration + Nest controller/module coverage), centralizing test helpers, and updating documentation to reflect the intended package architecture (notably: repository implementations living in separate DB packages).

Changes:

• Added extensive Jest tests across core, infra providers, and NestJS integration; introduced shared mocks/factories in test/test-utils.ts.
• Tightened Jest configuration (coverage reporting + thresholds) and updated TS config/types to support the new tests.
• Removed in-repo concrete repository implementations and updated infra exports/docs toward “schema reference only” + external DB packages; expanded top-level docs (README/CONTRIBUTING/CHANGELOG/changeset).

Reviewed changes

Copilot reviewed 24 out of 26 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
tsconfig.json	Adds node types to support Node globals in tests/build.
test/test-utils.ts	Introduces shared mocks/factories for tests to reduce duplication.
test/smoke.spec.ts	Expands smoke test to validate module exports/structure.
test/integration.test.ts	Adds Nest testing-module integration tests for end-to-end flows.
src/nest/module.test.ts	Adds unit tests for Nest module registration and DI wiring.
src/nest/decorators.test.ts	Adds tests for DI decorators and injection tokens.
src/nest/controllers/webhook.controller.test.ts	Adds unit tests for webhook controller behaviors.
src/nest/controllers/notification.controller.test.ts	Adds unit tests for REST controller behaviors/mappings.
src/infra/repositories/mongoose/notification.schema.ts	Adjusts optional-mongoose runtime schema typing behavior.
src/infra/repositories/mongoose/mongoose.repository.ts	Removes in-repo Mongoose repository implementation.
src/infra/repositories/index.ts	Limits infra repository exports to schema references and clarifies intent.
src/infra/repositories/in-memory/in-memory.repository.ts	Removes in-repo in-memory repository implementation.
src/infra/providers/providers.test.ts	Adds tests for infra providers (id/date/template/event emitters).
src/infra/index.ts	Updates infra layer docs to reflect schema-only repos + external DB packages.
src/infra/README.md	Updates infra documentation for external DB repos + schema reference guidance.
src/core/notification.service.test.ts	Adds broad unit test coverage for core NotificationService behaviors.
src/core/errors.test.ts	Adds unit tests for error classes and inheritance.
src/core/dtos.test.ts	Adds unit tests for DTO validation schemas and helpers.
package.json	Adds Nest testing deps to devDependencies.
package-lock.json	Updates lockfile for new devDependencies and transitive deps.
jest.config.ts	Expands test discovery patterns, adds coverage reporters/thresholds, tightens mock resets.
README.md	Replaces placeholder README with comprehensive package documentation and examples.
CONTRIBUTING.md	Replaces placeholders and adds testing/quality guidance.
CHANGELOG.md	Adds a changelog documenting testing/docs/quality work.
.github/instructions/testing.instructions.md	Adds guidance and examples for shared test utilities.
.changeset/notificationkit_71368.md	Updates changeset to describe the comprehensive testing + docs changes.