fix: Bump GGML to fix broken quantized matmul on Vulkan

flake.nix

@@ -0,0 +1,56 @@
+{
+  description = "qwen3-tts.cpp — dev environment (C++/GGML, CPU + Vulkan)";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+
+        # Vulkan toolchain needed to build ggml with -DGGML_VULKAN=ON:
+        # glslc/glslangValidator compile the .comp shaders, the loader +
+        # headers provide the API, spirv-tools links the shader pipeline.
+        vulkanInputs = [
+          pkgs.vulkan-headers
+          pkgs.vulkan-loader
+          pkgs.shaderc          # glslc
+          pkgs.glslang
+          pkgs.spirv-tools
+          pkgs.spirv-headers
+        ];
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = [
+            pkgs.cmake
+            pkgs.ninja
+            pkgs.pkg-config
+            pkgs.git
+            # Runtime/diagnostic helpers
+            pkgs.vulkan-tools     # vulkaninfo
+          ] ++ vulkanInputs;
+
+          # ggml's CMake finds Vulkan via the standard module; make sure the
+          # loader is also on the runtime path so the built CLI/libs resolve
+          # libvulkan when GGML_VULKAN is enabled.
+          LD_LIBRARY_PATH = pkgs.lib.makeLibraryPath [ pkgs.vulkan-loader ];
+
+          shellHook = ''
+            echo "qwen3-tts.cpp dev shell"
+            echo "  cmake:  $(cmake --version | head -1)"
+            echo "  glslc:  $(glslc --version 2>/dev/null | head -1)"
+            echo
+            echo "Build ggml (CPU+Vulkan):"
+            echo "  cmake -S ggml -B ggml/build -G Ninja -DCMAKE_BUILD_TYPE=Release -DGGML_VULKAN=ON"
+            echo "  cmake --build ggml/build -j"
+            echo "Build qwen3-tts:"
+            echo "  cmake -S . -B build -G Ninja -DCMAKE_BUILD_TYPE=Release"
+            echo "  cmake --build build -j"
+          '';
+        };
+      });
+}