-`New(logger logz.Logger, cfg Config) Component`: returns a pure-Go SQLite component backed by `modernc.org/sqlite`; no CGO required.
- Lifecycle hooks: `OnInit` opens the database, sets connection limits, and enforces `PRAGMA foreign_keys = ON`; startup fails if the pragma cannot be set. `OnStart` pings with a 5-second timeout. `OnStop` closes the connection.
-`NewUnitOfWork(logger logz.Logger, client Client) UnitOfWork`: wraps a `Client` to provide transactional `Do` semantics. When the client is the concrete `*sqliteComponent`, the write mutex is acquired for the duration of `Do` to serialise concurrent write transactions and prevent `SQLITE_BUSY`.
- Transaction context injection: the active `*sql.Tx` is stored under an unexported `ctxTxKey{}` context key; `GetExecutor` returns it when found, otherwise returns `*sql.DB`.
- WAL journal mode, 5-second busy timeout, and foreign key enforcement enabled by default via the `Pragmas` DSN suffix.
- Support for in-memory databases via `Config{Path: ":memory:"}` for test isolation.
### Design Notes
-`modernc.org/sqlite` (pure Go, no CGO) is used instead of `mattn/go-sqlite3`, enabling cross-compilation with `CGO_ENABLED=0` and no system library dependency.
- A `sync.Mutex` (`writeMu`) on the component serialises all `UnitOfWork.Do` calls, preventing `SQLITE_BUSY` errors that arise from SQLite's single-writer constraint without requiring callers to manage locking.
- Foreign key enforcement is applied both via the `_fk=true` DSN pragma and an explicit `PRAGMA foreign_keys = ON` statement in `OnInit`, ensuring enforcement is active regardless of driver-level pragma handling.
