Entry-Centric Data Model

Description

Implement the universal Entry data model, which represents any filesystem item (file, directory, symlink). Every Entry is designed for immediate metadata capability via a linked UserMetadata record, allowing users to tag and organize files the moment they are discovered.

Implementation Notes

• The core domain model will be defined in src/domain/entry.rs.
• The corresponding database entity will be implemented in src/infrastructure/database/entities/entry.rs.
• The EntryKind enum correctly differentiates between File, Directory, and Symlink.

Acceptance Criteria

• Entry struct exists and contains fields for metadata_id and content_id.
• The system can represent files and directories using a unified model.
• The database schema correctly reflects the Entry model.