feat(desktop): redirect writable data to ~/.cow for packaged app

Introduce get_data_root() driven by the COW_DATA_DIR env var so the
packaged desktop build stores config.json, run.log, user data and
WeChat credentials under ~/.cow — surviving app updates and keeping the
app bundle read-only. Source deployments leave COW_DATA_DIR unset and
fall back to the repo root, so existing behavior is unchanged.

common/cloud_client.py

@@ -21,7 +21,7 @@ from bridge.context import Context, ContextType
 from bridge.reply import Reply, ReplyType
 from common.log import logger
 from linkai import LinkAIClient, PushMsg
-from config import conf, pconf, plugin_config, available_setting, write_plugin_config, get_root
+from config import conf, pconf, plugin_config, available_setting, write_plugin_config, get_root, get_weixin_credentials_path
 from plugins import PluginManager
 import threading
 import time
@@ -336,9 +336,7 @@ class CloudClient(LinkAIClient):
     @staticmethod
     def _remove_weixin_credentials():
         """Remove the weixin token credentials file so next connect triggers QR login."""
-        cred_path = os.path.expanduser(
-            conf().get("weixin_credentials_path", "~/.weixin_cow_credentials.json")
-        )
+        cred_path = get_weixin_credentials_path()
         try:
             if os.path.exists(cred_path):
                 os.remove(cred_path)

common/log.py

@@ -1,8 +1,21 @@
 import logging
+import os
 import sys
 import io
 
 
+def _log_path():
+    # Mirror config.get_data_root() without importing config (avoids a circular
+    # import, since config imports this module). The desktop build sets
+    # COW_DATA_DIR (e.g. ~/.cow); source deployments fall back to CWD.
+    data_dir = os.environ.get("COW_DATA_DIR")
+    if data_dir:
+        data_dir = os.path.expanduser(data_dir)
+        os.makedirs(data_dir, exist_ok=True)
+        return os.path.join(data_dir, "run.log")
+    return "run.log"
+
+
 def _reset_logger(log):
     for handler in log.handlers:
         handler.close()
@@ -20,7 +33,7 @@ def _reset_logger(log):
             datefmt="%Y-%m-%d %H:%M:%S",
         )
     )
-    file_handle = logging.FileHandler("run.log", encoding="utf-8")
+    file_handle = logging.FileHandler(_log_path(), encoding="utf-8")
     file_handle.setFormatter(
         logging.Formatter(
             "[%(levelname)s][%(asctime)s][%(filename)s:%(lineno)d] - %(message)s",

common/tmp_dir.py

@@ -1,18 +1,21 @@
 import os
-import pathlib
 
+from common.utils import expand_path
 from config import conf
 
 
 class TmpDir(object):
-    """A temporary directory that is deleted when the object is destroyed."""
+    """Temporary directory for transient artifacts (e.g. synthesized voice).
 
-    tmpFilePath = pathlib.Path("./tmp/")
+    Resolves to ``<agent_workspace>/tmp`` (default ``~/cow/tmp``) so temp files
+    land inside the agent workspace instead of a CWD-relative ``./tmp``, which
+    is unreliable for the packaged desktop app where CWD is undefined.
+    """
 
     def __init__(self):
-        pathExists = os.path.exists(self.tmpFilePath)
-        if not pathExists:
-            os.makedirs(self.tmpFilePath)
+        ws_root = expand_path(conf().get("agent_workspace", "~/cow"))
+        self.tmpFilePath = os.path.join(ws_root, "tmp")
+        os.makedirs(self.tmpFilePath, exist_ok=True)
 
     def path(self):
         return str(self.tmpFilePath) + "/"