ci: update runner-image + repo path to public/ namespace

Repos moved to public/ on Gitea: public/runner-image (CI image)
and public/code-crispies (this repo). Updates workflow image refs,
spec hyperlinks, README, and compose tags.

.gitea/workflows/deploy.yml

@@ -19,7 +19,7 @@ on:
 # Required repository variable:
 #   DEPLOY_ENABLED      "true" to enable
 #
-# Image: git.librete.ch/libretech/code-crispies
+# Image: git.librete.ch/public/code-crispies
 #   main pushes  → :main + :sha-<short>
 #   tag pushes   → :<tag> + :latest
 
@@ -27,7 +27,7 @@ jobs:
   deploy:
     runs-on: ubuntu-latest
     container:
-      image: git.librete.ch/libretech/runner-image:v1
+      image: git.librete.ch/public/runner-image:v1
     timeout-minutes: 20
     if: ${{ vars.DEPLOY_ENABLED == 'true' }}
     steps:
@@ -44,7 +44,7 @@ jobs:
       - id: meta
         uses: docker/metadata-action@v5
         with:
-          images: ${{ secrets.REGISTRY }}/libretech/code-crispies
+          images: ${{ secrets.REGISTRY }}/public/code-crispies
           tags: |
             type=ref,event=branch
             type=ref,event=tag