Refactor release workflow to streamline file preparation and update README for clearer installation instructions

.forgejo/workflows/release.yaml

@@ -11,11 +11,9 @@ jobs:
         uses: actions/checkout@v4
       - name: Prepare files
         run: |
-          mkdir -p /tmp/micromail /tmp/release
-          cp package.json /tmp/micromail/
-          cp -r micromail /tmp/micromail/
-          cd /tmp/micromail
-          tar -czvf /tmp/release/micromail.tar.gz .
+          mkdir -p /tmp/release
+          cp package.json /tmp/release/
+          cp -r micromail /tmp/release/
       - name: Make release
         uses: actions/forgejo-release@v2.6.0
         with: