feat(release): make the signing-free install work with nothing but Windows

The manual install path still needed 7-Zip, which the target machine does not
have, so "installable without a certificate" was not yet true.

The channel now also publishes the app as byte-split zip parts, and the install
script joins them and extracts with the built-in Windows Expand-Archive after
verifying every part and the joined archive. Version 1.3.1 republishes the
channel from a single build, because a version's artifacts can only match one
build and published volumes are never overwritten.

apps/desktop/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@d3ro/desktop",
-  "version": "1.3.0",
+  "version": "1.3.1",
   "productName": "d3ro-voice",
   "description": "로컬 AI 음성 어시스턴트 (Electron)",
   "main": "./out/main/index.js",