release: align desktop versions, harden tag check

tauri.conf.json and apps/desktop/package.json lagged at 0.5.0, so
v0.6.0 desktop bundles were labeled 0.5.0. Verify job now checks all
three version sources match the tag.

Authored By: TDvorak <[email protected]>

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

apps/desktop/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@primora/desktop",
-  "version": "0.5.0",
+  "version": "0.6.0",
   "private": true,
   "description": "Primora desktop shell — thin Tauri client for a self-hosted deployment",
   "scripts": {