feat: add Gitea actions to sync releases to GitHub

Add two new workflows:
- sync-release.yml: automatically mirrors releases (with assets) to GitHub when published on Gitea
- backfill-releases.yml: manual workflow to bulk-sync all existing Gitea releases to GitHub

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

.gitea/workflows/backfill-releases.yml

@@ -0,0 +1,83 @@
+name: Backfill Releases to GitHub
+
+on:
+  workflow_dispatch:
+
+jobs:
+  backfill:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Backfill all Gitea releases to GitHub
+        env:
+          GH_PAT: ${{ secrets.GH_PAT }}
+          GITEA_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
+          GITEA_API: https://repo.anhonesthost.net/api/v1
+          GITEA_REPO: cybercovellc/triple-c
+          GITHUB_REPO: shadowdao/triple-c
+        run: |
+          set -e
+
+          echo "==> Fetching releases from Gitea..."
+          RELEASES=$(curl -sf \
+            -H "Authorization: token $GITEA_TOKEN" \
+            "$GITEA_API/repos/$GITEA_REPO/releases?limit=50")
+
+          echo "$RELEASES" | jq -c '.[]' | while read release; do
+            TAG=$(echo "$release" | jq -r '.tag_name')
+            NAME=$(echo "$release" | jq -r '.name')
+            BODY=$(echo "$release" | jq -r '.body')
+            IS_PRERELEASE=$(echo "$release" | jq -r '.prerelease')
+            IS_DRAFT=$(echo "$release" | jq -r '.draft')
+
+            EXISTS=$(curl -sf \
+              -H "Authorization: Bearer $GH_PAT" \
+              -H "Accept: application/vnd.github+json" \
+              "https://api.github.com/repos/$GITHUB_REPO/releases/tags/$TAG" \
+              -o /dev/null -w "%{http_code}" || true)
+
+            if [ "$EXISTS" = "200" ]; then
+              echo "==> Skipping $TAG (already exists on GitHub)"
+              continue
+            fi
+
+            echo "==> Creating release $TAG..."
+            RESPONSE=$(curl -sf -X POST \
+              -H "Authorization: Bearer $GH_PAT" \
+              -H "Accept: application/vnd.github+json" \
+              -H "Content-Type: application/json" \
+              https://api.github.com/repos/$GITHUB_REPO/releases \
+              -d "{
+                \"tag_name\": \"$TAG\",
+                \"name\": \"$NAME\",
+                \"body\": $(echo "$BODY" | jq -Rs .),
+                \"draft\": $IS_DRAFT,
+                \"prerelease\": $IS_PRERELEASE
+              }")
+
+            UPLOAD_URL=$(echo "$RESPONSE" | jq -r '.upload_url' | sed 's/{?name,label}//')
+
+            echo "$release" | jq -c '.assets[]?' | while read asset; do
+              ASSET_NAME=$(echo "$asset" | jq -r '.name')
+              ASSET_ID=$(echo "$asset" | jq -r '.id')
+
+              echo "  ==> Downloading $ASSET_NAME..."
+              curl -sfL -o "/tmp/$ASSET_NAME" \
+                -H "Authorization: token $GITEA_TOKEN" \
+                "$GITEA_API/repos/$GITEA_REPO/releases/assets/$ASSET_ID"
+
+              echo "  ==> Uploading $ASSET_NAME to GitHub..."
+              ENCODED_NAME=$(python3 -c "import urllib.parse, sys; print(urllib.parse.quote(sys.argv[1]))" "$ASSET_NAME")
+              curl -sf -X POST \
+                -H "Authorization: Bearer $GH_PAT" \
+                -H "Accept: application/vnd.github+json" \
+                -H "Content-Type: application/octet-stream" \
+                --data-binary "@/tmp/$ASSET_NAME" \
+                "$UPLOAD_URL?name=$ENCODED_NAME"
+
+              echo "    Uploaded: $ASSET_NAME"
+            done
+
+            echo "==> Done: $TAG"
+          done
+
+          echo "==> Backfill complete."