Release v0.2.0

Bump version to 0.2.0 across package.json, tauri.conf.json and Cargo.toml.
First signed release published to Gitea (tags v0.2.0 + updater/latest.json);
auto-updater endpoint verified live.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

package.json

@@ -1,7 +1,7 @@
 {
   "name": "exbyte-depot",
   "private": true,
-  "version": "0.1.0",
+  "version": "0.2.0",
   "type": "module",
   "scripts": {
     "dev": "vite",