docs: update README and CI workflow to clarify Gitea Registry login process and improve Docker image build conditions, including handling of secrets and environment variables

.gitea/workflows/ci.yaml

@@ -161,43 +161,30 @@ jobs:
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
-      - name: Prepare registry (REGISTRY in env + outputs)
+      - name: Prepare image metadata
         id: meta
-        env:
-          HOST: ${{ secrets.GITEA_REGISTRY_HOST }}
         run: |
           set -euo pipefail
           owner_lc="$(echo '${{ github.repository_owner }}' | tr '[:upper:]' '[:lower:]')"
           echo "owner_lc=$owner_lc" >> "$GITHUB_OUTPUT"
           short_sha="$(echo '${{ github.sha }}' | cut -c1-7)"
           echo "short_sha=$short_sha" >> "$GITHUB_OUTPUT"
-          if [ -z "${HOST:-}" ]; then
-            echo "GITEA_REGISTRY_HOST not set — build without push."
-            echo "docker_push=false" >> "$GITHUB_OUTPUT"
-            echo "REGISTRY=" >> "$GITHUB_ENV"
-          else
-            h="$HOST"
-            h="${h#https://}"
-            h="${h#http://}"
-            h="${h%/}"
-            echo "docker_push=true" >> "$GITHUB_OUTPUT"
-            echo "REGISTRY=$h" >> "$GITHUB_ENV"
-          fi
+          echo "docker_push=true" >> "$GITHUB_OUTPUT"
 
       - name: Log in to Gitea Registry
-        if: steps.meta.outputs.docker_push == 'true' && secrets.ACTIONS_PAT != ''
+        if: steps.meta.outputs.docker_push == 'true'
         uses: docker/login-action@v3
         with:
-          registry: ${{ env.REGISTRY }}
+          registry: git.shts.su
           username: ${{ gitea.actor }}
-          password: ${{ secrets.ACTIONS_PAT }}
+          # PAT репозитория или встроенный токен job (нужны права на пакеты в настройках Actions).
+          password: ${{ secrets.ACTIONS_PAT || gitea.token }}
 
       - name: Build and push ${{ matrix.image }}
         env:
           OWNER_LC: ${{ steps.meta.outputs.owner_lc }}
           SHORT_SHA: ${{ steps.meta.outputs.short_sha }}
           DO_PUSH: ${{ steps.meta.outputs.docker_push }}
-          PAT_OK: ${{ secrets.ACTIONS_PAT != '' }}
           DF: ${{ matrix.dockerfile }}
           IMAGE: ${{ matrix.image }}
           BIN: ${{ matrix.bin }}
@@ -214,8 +201,8 @@ jobs:
             BUILD_ARGS+=(--build-arg "INSTALL_BIRDC=${BIRDC:-0}")
           fi
 
-          if [ "$DO_PUSH" = "true" ] && [ -n "${REGISTRY:-}" ] && [ "$PAT_OK" = "true" ]; then
-            IMG="${REGISTRY}/${OWNER_LC}/${IMAGE}"
+          if [ "$DO_PUSH" = "true" ]; then
+            IMG="git.shts.su/${OWNER_LC}/${IMAGE}"
             docker buildx build \
               --platform linux/amd64 \
               --file "$DF" \