add registry login using built-in gitea.token

Uses gitea.actor and gitea.token for automatic authentication
to the container registry.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.gitea/workflows/docker-build.yml

@@ -9,6 +9,12 @@ jobs:
     name: 🏗️ Docker builder (latest from master) 🏗️
     runs-on: dind
     steps:
+      - name: "[docker] registry login"
+        uses: docker/login-action@v2
+        with:
+          registry: git.cynarski.pl
+          username: ${{ gitea.actor }}
+          password: ${{ gitea.token }}
       - name: "[code] repository checkout"
         uses: actions/checkout@v3
       - name: "[ledo] Image build"

.gitea/workflows/docker-tag.yml

@@ -9,6 +9,12 @@ jobs:
     name: 🏗️ Docker builder release tag 🏗️
     runs-on: dind
     steps:
+      - name: "[docker] registry login"
+        uses: docker/login-action@v2
+        with:
+          registry: git.cynarski.pl
+          username: ${{ gitea.actor }}
+          password: ${{ gitea.token }}
       - name: "[code] repository checkout"
         uses: actions/checkout@v3
       - name: "[ledo] Image build"