refactor(opencode): replace Bun shell in core flows (#16286)

packages/opencode/src/util/archive.ts

@@ -1,5 +1,5 @@
-import { $ } from "bun"
 import path from "path"
+import { Process } from "./process"
 
 export namespace Archive {
   export async function extractZip(zipPath: string, destDir: string) {
@@ -8,9 +8,10 @@ export namespace Archive {
       const winDestDir = path.resolve(destDir)
       // $global:ProgressPreference suppresses PowerShell's blue progress bar popup
       const cmd = `$global:ProgressPreference = 'SilentlyContinue'; Expand-Archive -Path '${winZipPath}' -DestinationPath '${winDestDir}' -Force`
-      await $`powershell -NoProfile -NonInteractive -Command ${cmd}`.quiet()
-    } else {
-      await $`unzip -o -q ${zipPath} -d ${destDir}`.quiet()
+      await Process.run(["powershell", "-NoProfile", "-NonInteractive", "-Command", cmd])
+      return
     }
+
+    await Process.run(["unzip", "-o", "-q", zipPath, "-d", destDir])
   }
 }