test: add mock downstream email adapter

Author: LalaSkye

enterprise-execution-readiness/adapters/mock_email_adapter.py

@@ -0,0 +1,33 @@
+"""
+Mock downstream email adapter for ESP-001.
+
+This adapter is intentionally synthetic and in-memory.
+It proves whether the send connector would be called inside the test harness.
+It does not prove live SMTP/API non-execution.
+"""
+
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import Any, Dict, List
+
+
+@dataclass
+class MockEmailAdapter:
+    """In-memory stand-in for an external email connector."""
+
+    sent_messages: List[Dict[str, Any]] = field(default_factory=list)
+
+    def send(self, *, recipient: str, payload_hash: str, actor: str) -> Dict[str, Any]:
+        event = {
+            "recipient": recipient,
+            "payload_hash": payload_hash,
+            "actor": actor,
+            "dispatched": True,
+        }
+        self.sent_messages.append(event)
+        return event
+
+    @property
+    def send_call_count(self) -> int:
+        return len(self.sent_messages)