fix(windows): inherit all system environment variables into MCP runner for Windows (#7054)

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* fix(stdio): improve Windows environment setup for subprocesses

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)
-Add `show_console` option to control `CREATE_NO_WINDOW` flag.Default remains hidden (backward compatible) but can be overridden.

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* fix(stdio): improve Windows environment setup for subprocesses 修复（标准输入输出）：改进 Windows 环境设置以支持子进程

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)
-Add `show_console` option to control `CREATE_NO_WINDOW` flag.Default remains hidden (backward compatible) but can be overridden.

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* fix(stdio): improve Windows environment setup for subprocesses 修复（标准输入输出）：改进 Windows 环境设置以支持子进程

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)
-Add `no_console` option to control `CREATE_NO_WINDOW` flag.Default remains hidden (backward compatible) but can be overridden.

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* fix(stdio): improve Windows environment setup for subprocesses 修复（标准输入输出）：改进 Windows 环境设置以支持子进程

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)
-Add `no_console` option to control `CREATE_NO_WINDOW` flag.Default remains hidden (backward compatible) but can be overridden.

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* fix(windows): inherit all system environment variables for subprocesses

- Merge environment variables case‑insensitively
- Auto‑configure dotnet PATH and suppress console window
- Keep PATHEXT inheritance (from old implementation)
- No longer handle as a special case for C#.

Replaces the minimal PATHEXT fix with a robust solution that resolves
common Windows subprocess issues, especially for .NET servers.

* chore: ruff format

---------

Co-authored-by: Soulter <905617992@qq.com>

astrbot/core/agent/mcp_client.py

@@ -51,18 +51,29 @@ def _prepare_stdio_env(config: dict) -> dict:
     """Preserve Windows executable resolution for stdio subprocesses."""
     if sys.platform != "win32":
         return config
-
-    pathext = os.environ.get("PATHEXT")
-    if not pathext:
-        return config
-
     prepared = config.copy()
     env = dict(prepared.get("env") or {})
-    env.setdefault("PATHEXT", pathext)
+    env = _merge_environment_variables(env)
     prepared["env"] = env
     return prepared
 
 
+def _merge_environment_variables(env: dict) -> dict:
+    """合并环境变量，处理Windows不区分大小写的情况"""
+    merged = env.copy()
+
+    # 将用户环境变量转换为统一的大小写形式便于比较
+    user_keys_lower = {k.lower(): k for k in merged.keys()}
+
+    for sys_key, sys_value in os.environ.items():
+        sys_key_lower = sys_key.lower()
+        if sys_key_lower not in user_keys_lower:
+            # 使用系统环境变量中的原始大小写
+            merged[sys_key] = sys_value
+
+    return merged
+
+
 async def _quick_test_mcp_connection(config: dict) -> tuple[bool, str]:
     """Quick test MCP server connectivity"""
     import aiohttp