This commit introduces the `MergeWork` command, a new feature to merge two `Work` entities, their associations, and their statistics. The entire operation is performed atomically within a database transaction to ensure data integrity.
Key changes include:
- A new `MergeWork` method in `internal/app/work/commands.go`.
- An `Add` method on the `WorkStats` entity for combining statistics.
- A new `GetWithAssociationsInTx` method on the `WorkRepository` to fetch entities within a transaction.
- A comprehensive integration test using an in-memory SQLite database to validate the merge logic.
This commit also consolidates all scattered TODOs and build issues from `TODO.md` and `BUILD_ISSUES.md` into a single, actionable `TASKS.md` file. The legacy documentation files have been removed to create a single source of truth for pending work.
This commit isolates the `Work` aggregate into its own package at `internal/domain/work`, following the first step of the refactoring plan in `refactor.md`.
- The `Work` struct, related types, and the `WorkRepository` interface have been moved to the new package.
- A circular dependency between `domain` and `work` was resolved by moving the `AnalyticsRepository` to the `app` layer.
- All references to the moved types have been updated across the entire codebase to fix compilation errors.
- Test files, including mocks and integration tests, have been updated to reflect the new structure.
