map_proposal
function map_proposal( proposal: proposal): (id: rowid, author_id: byte_array, author_type: citizen_types, category: text, title: text, description: text, state: proposal_state, duration: integer, start_timestamp: integer, end_timestamp: integer, options: list<(option_id: rowid, proposal_id: rowid, option: text, total_vote: big_integer, (command_id: rowid, name: text, description: text, is_executed: boolean)?)>, winner_option: text, approvals_response?)