feat: unify group policy allowlists

docs/imessage.md

@@ -27,6 +27,8 @@ Status: external CLI integration. No daemon.
     cliPath: "imsg",
     dbPath: "~/Library/Messages/chat.db",
     allowFrom: ["+15555550123", "user@example.com", "chat_id:123"],
+    groupPolicy: "open",
+    groupAllowFrom: ["chat_id:123"],
     includeAttachments: false,
     mediaMaxMb: 16,
     service: "auto",
@@ -37,6 +39,8 @@ Status: external CLI integration. No daemon.
 
 Notes:
 - `allowFrom` accepts handles (phone/email) or `chat_id:<id>` entries.
+- `groupPolicy` controls group handling (`open|disabled|allowlist`).
+- `groupAllowFrom` accepts the same entries as `allowFrom`.
 - `service` defaults to `auto` (use `imessage` or `sms` to pin).
 - `region` is only used for SMS targeting.