chore: 改名同步 TransPyV -> ViperC（源码/配置内的纯替换）

MultiInheritTest/App/main.vp

@@ -120,7 +120,7 @@ class Vec2M:
 
 
 class Vec2Extra:
-    # Field access uses the defining class's fields (TPV model); does not
+    # Field access uses the defining class's fields (VPC model); does not
     # reference Vec2M's x/y (cross-parent field access is out of scope here).
     def extra_val(self) -> CInt:
         return 7

MultiInheritTest/project.json

@@ -3,7 +3,7 @@
     "name": "MultiInheritTest",
     "version": "1.0.0",
     "source_dir": "./App",
-    "build_dir": "./.tpv_build",
+    "build_dir": "./__vpcbuild__",
     "compiler": {
         "cmd": "llc",
         "flags": [