"""Add lead-back guarantee columns to lead_forwards.

guarantee_claimed_at: ISO timestamp when supplier claimed the guarantee refund.
guarantee_contact_method: how the supplier tried to reach the lead (email/phone/both).
Status 'no_response' added to lead_forwards.status by convention (no CHECK constraint change
needed — existing status TEXT column accepts any value).
"""


def up(conn):
    conn.execute(
        "ALTER TABLE lead_forwards ADD COLUMN guarantee_claimed_at TEXT"
    )
    conn.execute(
        "ALTER TABLE lead_forwards ADD COLUMN guarantee_contact_method TEXT"
    )
