Fix CI: remove invalid "updater" bundle target + update release notes

"updater" is not a valid Tauri 2.x bundle target — the auto-updater
is configured as a plugin, not a bundle format. This was causing
exit code 1 on all three platforms for the v0.1.6 build.

Also updates release notes in the workflow for v0.1.7.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src-tauri/tauri.conf.json

@@ -25,7 +25,7 @@
   },
   "bundle": {
     "active": true,
-    "targets": ["deb", "rpm", "nsis", "msi", "dmg", "updater"],
+    "targets": ["deb", "rpm", "nsis", "msi", "dmg"],
     "icon": [
       "icons/32x32.png",
       "icons/128x128.png",