fix(whatsapp): add free_response_chats, mention stripping, and interactive message unwrapping

Address feature gaps vs Telegram/Discord/Mattermost adapters:
- free_response_chats whitelist to bypass mention gating per-group
- strip bot @phone mentions from body before forwarding to agent
- unwrap templateMessage/buttonsMessage/listMessage in bridge
- info-level log on successful mention pattern compilation
- use module-level json import instead of inline import in config
- eliminate double _normalize_whatsapp_id call via walrus operator
- hoist botIds computation outside per-message loop in bridge

tests/gateway/test_whatsapp_group_gating.py

@@ -4,7 +4,7 @@ from unittest.mock import AsyncMock
 from gateway.config import Platform, PlatformConfig, load_gateway_config
 
 
-def _make_adapter(require_mention=None, mention_patterns=None):
+def _make_adapter(require_mention=None, mention_patterns=None, free_response_chats=None):
     from gateway.platforms.whatsapp import WhatsAppAdapter
 
     extra = {}
@@ -12,6 +12,8 @@ def _make_adapter(require_mention=None, mention_patterns=None):
         extra["require_mention"] = require_mention
     if mention_patterns is not None:
         extra["mention_patterns"] = mention_patterns
+    if free_response_chats is not None:
+        extra["free_response_chats"] = free_response_chats
 
     adapter = object.__new__(WhatsAppAdapter)
     adapter.platform = Platform.WHATSAPP
@@ -25,6 +27,7 @@ def _group_message(body="hello", **overrides):
     data = {
         "isGroup": True,
         "body": body,
+        "chatId": "120363001234567890@g.us",
         "mentionedIds": [],
         "botIds": ["15551230000@s.whatsapp.net", "15551230000@lid"],
         "quotedParticipant": "",
@@ -95,3 +98,45 @@ def test_config_bridges_whatsapp_group_settings(monkeypatch, tmp_path):
     assert config.platforms[Platform.WHATSAPP].extra["mention_patterns"] == [r"^\s*chompy\b"]
     assert __import__("os").environ["WHATSAPP_REQUIRE_MENTION"] == "true"
     assert json.loads(__import__("os").environ["WHATSAPP_MENTION_PATTERNS"]) == [r"^\s*chompy\b"]
+
+
+def test_free_response_chats_bypass_mention_gating():
+    adapter = _make_adapter(
+        require_mention=True,
+        free_response_chats=["120363001234567890@g.us"],
+    )
+
+    assert adapter._should_process_message(_group_message("hello everyone")) is True
+
+
+def test_free_response_chats_does_not_bypass_other_groups():
+    adapter = _make_adapter(
+        require_mention=True,
+        free_response_chats=["999999999999@g.us"],
+    )
+
+    assert adapter._should_process_message(_group_message("hello everyone")) is False
+
+
+def test_dm_always_passes_even_with_require_mention():
+    adapter = _make_adapter(require_mention=True)
+
+    dm = {"isGroup": False, "body": "hello", "botIds": [], "mentionedIds": []}
+    assert adapter._should_process_message(dm) is True
+
+
+def test_mention_stripping_removes_bot_phone_from_body():
+    adapter = _make_adapter(require_mention=True)
+
+    data = _group_message("@15551230000 what is the weather?")
+    cleaned = adapter._clean_bot_mention_text(data["body"], data)
+    assert "15551230000" not in cleaned
+    assert "weather" in cleaned
+
+
+def test_mention_stripping_preserves_body_when_no_mention():
+    adapter = _make_adapter(require_mention=True)
+
+    data = _group_message("just a normal message")
+    cleaned = adapter._clean_bot_mention_text(data["body"], data)
+    assert cleaned == "just a normal message"