CREATE TABLE interactions (
    id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
    contact_id BIGINT UNSIGNED NOT NULL,
    type VARCHAR(50) NOT NULL DEFAULT 'note',
    notes TEXT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (contact_id) REFERENCES contacts(id) ON DELETE CASCADE,
    INDEX idx_interactions_contact (contact_id),
    INDEX idx_interactions_type (type)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;