"""Email sender port - provider-agnostic interface."""

from __future__ import annotations

from typing import Optional, Protocol


class EmailSender(Protocol):
    def send(
        self,
        to: str | list[str],
        subject: str,
        html: Optional[str] = None,
        text: Optional[str] = None,
    ) -> bool:
        """Send email. Returns True on success."""
        ...