fix(webview2): fall back to byte[] assembly load and guard instance lock

Assembly.LoadFrom can fail on volumes .NET misclassifies as remote; fall back to Assembly.Load(byte[]). Broaden exception handling to BaseException for pythonnet, and skip WebView2 warmup/taskkill when the instance lock is held by another process.

core/webview2.py

@@ -158,7 +158,18 @@ def get_environment(app):
             pass
         import clr
         global _System
-        clr.AddReference(CORE_DLL)
+        # 🐛 部分机器（本机 D: 卷）.NET Framework 把工程所在本地卷误判为
+        #    “网络位置”，clr.AddReference（= Assembly.LoadFrom）报 0x80131515。
+        #    快路径保持 LoadFrom（正常机器行为不变）；失败回落 Assembly.Load(byte[])，
+        #    字节加载不做路径信任分类（本机实测：D: 字节加载 OK，类型解析 OK）。
+        try:
+            clr.AddReference(CORE_DLL)
+        except BaseException as _ex:  # pythonnet 的 .NET 异常未必是 Python Exception 子类
+            _msg = str(_ex).splitlines()[0][:120] if str(_ex) else type(_ex).__name__
+            print(f"[WV2] AddReference 路径加载失败（{_msg}）→ 回落 Assembly.Load(byte[])")
+            from System.Reflection import Assembly as _Assembly
+            with open(CORE_DLL, "rb") as _f:
+                _Assembly.Load(_f.read())
         import System
         _System = System
         from Microsoft.Web.WebView2.Core import CoreWebView2Environment
@@ -166,7 +177,7 @@ def get_environment(app):
         _env = _pump_wait(CoreWebView2Environment.CreateAsync(None, None, None), app)
         print(f"[WV2] {_ts()} Runtime ready: {_env.BrowserVersionString}")
         return _env
-    except Exception as ex:
+    except BaseException as ex:  # pythonnet/.NET 异常未必是 Exception 子类，必须 BaseException
         _env = None
         print(f"[WV2] init failed → fallback to QtWebEngine: {ex}")
         return None