fix: improve release scripts with .env loading and idempotent publish

Scripts now auto-load .env for GITEA_TOKEN, handle re-publishing
by deleting existing versions first, and release.sh does build +
publish + install in one command.

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

package.json

@@ -17,7 +17,8 @@
     "db:down": "docker compose -f deploy/docker-compose.yml down",
     "typecheck": "tsc --build",
     "rpm:build": "bash scripts/build-rpm.sh",
-    "rpm:publish": "bash scripts/publish-rpm.sh"
+    "rpm:publish": "bash scripts/publish-rpm.sh",
+    "release": "bash scripts/release.sh"
   },
   "engines": {
     "node": ">=20.0.0",