first commit

Co-Authored-By: Claude <noreply@anthropic.com>

sms/exceptions.py

@@ -0,0 +1,26 @@
+"""Exception hierarchy for the voip.ms SMS client."""
+
+
+class VoipMsError(Exception):
+    """Base error for any failure talking to the voip.ms API."""
+
+
+class VoipMsAuthError(VoipMsError):
+    """Authentication / IP-whitelist problem reported by voip.ms."""
+
+
+class VoipMsApiError(VoipMsError):
+    """voip.ms returned a non-success `status` in the response body."""
+
+    def __init__(self, message: str, code: str | None = None) -> None:
+        super().__init__(message)
+        self.code = code
+
+
+class VoipMsRateLimitError(VoipMsError):
+    """Local daily-send guard refused the request before it was sent."""
+
+    def __init__(self, message: str, *, limit: int, used_today: int) -> None:
+        super().__init__(message)
+        self.limit = limit
+        self.used_today = used_today