bump dawn version to c469d593ac and remove WebGPU-distribution from third_party

Author: austinvhuang

.gitmodules

@@ -1,7 +1,3 @@
-[submodule "third_party/local/WebGPU-distribution"]
-	path = third_party/local/WebGPU-distribution
-	url = https://github.com/eliemichel/WebGPU-distribution.git
-	branch = dawn
 [submodule "third_party/llm.c"]
 	path = third_party/llm.c
 	url = https://github.com/karpathy/llm.c

setup.py

@@ -61,8 +61,8 @@ def download_dawn(os_name):
         "Linux": "third_party/lib/libwebgpu_dawn.so",
     }
     url_map = {
-        "macOS": "https://github.com/austinvhuang/dawn-artifacts/releases/download/0.2.0/libwebgpu_dawn.dylib",
-        "Linux": "https://github.com/austinvhuang/dawn-artifacts/releases/download/0.2.0/libwebgpu_dawn.so",
+        "macOS": "https://github.com/austinvhuang/dawn-artifacts/releases/download/0.2.0-pre2/libwebgpu_dawn.dylib",
+        "Linux": "https://github.com/austinvhuang/dawn-artifacts/releases/download/0.2.0-pre2/libwebgpu_dawn.so",
     }
 
     outfile = outfile_map.get(os_name)

third_party/headers/webgpu/README.md

@@ -1 +1,5 @@
-webgpu.h from dawn build: _deps/dawn-build/gen/include/dawn/
+0.2.0
+
+Dawn Commit Hash: c469d593ac 
+
+webgpu.h from dawn build directory: gen/include/dawn/webgpu.h