implements #54: implements note service

[alexander-wudy]

Note Service Implementation

This PR implements the core backend features and integration tests for the Note Service, making it ready for production.

Highlights

• Core CRUD & Auditing: Completed all CRUD operations with automatic creation and modification timestamping.
• Security & Ownership: Secured all API endpoints using JWT authentication and enforced strict ownership checks so users can only access their own notes.
• Database & Indexing: Created the initial database schema with non-null constraints and added database indexing on owner queries for optimized performance.
• OpenAPI Compliance & Tests: Added 21 integration tests validating that all controller endpoints conform strictly to the OpenAPI schema.

[w-richter]

PR review — Note Service implementation

[w-richter]

Note toNote(CreateNoteRequest request, long userId) has no explicit @Mapping for userId. Relies on implicit parameter-name matching that breaks silently if the parameter is renamed.

[w-richter]

Write methods (createNote, updateNote, deleteNote) are not annotated with @Transactional. repository.save() commits before the subsequent mapper call, and entities loaded via getNoteEntity() may detach between findById() and save()/delete().

[alexander-wudy]

I also added @Transactional(readOnly = true) to read methods. Thanks for the heads up

[w-richter]

IllegalAccessPair.toString() is dead code. The parent constructor builds its message from pair.noteId and pair.ownerId directly, never calling toString().

[w-richter]

CreateNoteResponse, GetNoteResponse, and UpdateNoteResponse wrap IdentifiedTimestampedNote in allOf with an empty type: object that adds no constraints.

[w-richter]

The title column is VARCHAR(255) in Liquibase and content is TEXT, but the entity has no Bean Validation annotations (@Size, @NotBlank). A title exceeding 255 characters would produce a database constraint violation (500) instead of a validation error (400). Consider adding @Size(max = 255) on title and @NotBlank on both fields in a follow-up.

[w-richter]

The title column is VARCHAR(255) in Liquibase and content is TEXT, but the entity has no Bean Validation annotations (@Size, @NotBlank). A title exceeding 255 characters would produce a database constraint violation (500) instead of a validation error (400). Consider adding @Size(max = 255) on title and @NotBlank on both fields in a follow-up.

[alexander-wudy]

description should be able to be left blank, in case someone just wants to set some title to a note

[w-richter]

lgtm now