feat: add Windows ARM64 build support for CLI and VS Code extension

- Add win32/arm64 target to packages/opencode/script/build.ts
- Add win32-arm64 target to packages/kilo-vscode/script/build.ts and publish.ts
- Add @parcel/watcher-win32-arm64@2.5.1 optional dev dependency to packages/opencode/package.json
- Update RELEASING.md to document win32-arm64 CLI and VSIX targets

packages/opencode/script/build.ts

@@ -117,6 +117,12 @@ const allTargets: {
     arch: "x64",
     avx2: false,
   },
+  // kilocode_change start - added Windows ARM64 target
+  {
+    os: "win32",
+    arch: "arm64",
+  },
+  // kilocode_change end
 ]
 
 const targets = singleFlag