Fix Windows Python spawning

src/setup-local-ai.ts

@@ -10,6 +10,7 @@ async function run(command: string, args: string[], extraEnv?: NodeJS.ProcessEnv
   await new Promise<void>((resolve, reject) => {
     const child = spawn(command, args, {
       stdio: "inherit",
+      shell: process.platform === "win32",
       env: {
         ...process.env,
         ...extraEnv,
@@ -31,6 +32,7 @@ async function ensurePip(pythonBin: string, env: NodeJS.ProcessEnv): Promise<voi
   await new Promise<void>((resolve, reject) => {
     const child = spawn(pythonBin, ["-m", "pip", "--version"], {
       stdio: "ignore",
+      shell: process.platform === "win32",
       env,
     });
     child.on("exit", (code) => {