docs: apply fleet-template (16-artifact scaffold)

Adds missing standard artifacts:
- README.md (if missing)
- AGENTS.md (AI agent contract)
- PLAN.md (current sprint)
- STATUS.md (where we are)
- DEVELOPMENT.md (dev workflow)
- DEPLOYMENT.md (deploy procedure)
- TESTING.md (test strategy)
- DECISIONS.md (ADR index + templates)
- .github/CODEOWNERS
- .github/workflows/ci.yml

Preserves all existing artifacts.

Refs: RugMunchMedia/fleet-template

tests/test_alerter.py

@@ -0,0 +1,46 @@
+"""Tests for multi-channel alerting."""
+
+from alerter import (
+    _send_discord,
+    _send_slack,
+    _send_teams,
+    _send_telegram,
+    send_alert,
+)
+
+
+def test_send_alert_unknown_channel() -> None:
+    import asyncio
+
+    result = asyncio.run(send_alert("unknown", "Test", "Message", {}))
+    assert result["success"] is False
+    assert "unknown" in result["error"]
+
+
+def test_send_slack_no_webhook() -> None:
+    import asyncio
+
+    result = asyncio.run(_send_slack("Test", "Message", {}, "info"))
+    assert result["success"] is False
+
+
+def test_send_discord_no_webhook() -> None:
+    import asyncio
+
+    result = asyncio.run(_send_discord("Test", "Message", {}, "info"))
+    assert result["success"] is False
+
+
+def test_send_teams_no_webhook() -> None:
+    import asyncio
+
+    result = asyncio.run(_send_teams("Test", "Message", {}, "info"))
+    assert result["success"] is False
+
+
+def test_send_telegram_no_creds() -> None:
+    import asyncio
+
+    result = asyncio.run(_send_telegram("Test", "Message", {}, "info"))
+    assert result["success"] is False
+    assert "bot_token" in result["error"]