Fix CI: delete existing release before creating a new one

Prevents "Release has no Tag" error when re-running a build for
a tag that already has a release.

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

.forgejo/workflows/release.yml

@@ -152,6 +152,17 @@ jobs:
           **Windows** : Téléchargez le fichier \`.exe\` ci-dessous.
           **Linux** : Téléchargez le fichier \`.deb\` ou \`.AppImage\` ci-dessous."
 
+          # Delete existing release for this tag (if any) to allow re-creation
+          EXISTING=$(curl -s "${API_URL}/repos/${REPO}/releases/tags/${TAG}" \
+            -H "Authorization: token ${FORGEJO_TOKEN}")
+          EXISTING_ID=$(echo "$EXISTING" | jq -r '.id // empty')
+          if [ -n "$EXISTING_ID" ]; then
+            echo "Deleting existing release ID: $EXISTING_ID"
+            curl -s -X DELETE \
+              "${API_URL}/repos/${REPO}/releases/${EXISTING_ID}" \
+              -H "Authorization: token ${FORGEJO_TOKEN}"
+          fi
+
           # Create release
           RELEASE_RESPONSE=$(curl -s -X POST \
             "${API_URL}/repos/${REPO}/releases" \