DuckDB Project Tracking Administration

DuckDB Project Tracking Administration: a task in repo2rlenv-seta-evol (Harbor dataset). Table members : id INTEGER PRIMARY KEY, username VARCHAR NOT NULL UNIQUE, email VARCHAR NOT NULL, role VARCHAR NOT NULL DEFAULT 'contributor', active INTEGER NOT NULL DEFAULT 1, joined at VARCHAR NOT NULL

The task

**Table `members`**: `id INTEGER PRIMARY KEY, username VARCHAR NOT NULL UNIQUE, email VARCHAR NOT NULL, role VARCHAR NOT NULL DEFAULT 'contributor', active INTEGER NOT NULL DEFAULT 1, joined_at VARCHAR NOT NULL`

Part of FineEnvs/repo2rlenv-seta-evol.