chore: Update CI workflow to use self-hosted runners for Docker builds

### Summary of Changes
- Changed the runner configuration for all build jobs in the CI workflow from `ubuntu-latest` to `self-hosted`, ensuring that builds utilize self-hosted infrastructure.

### Expected Results
- Improved build performance and resource management by leveraging self-hosted runners, aligning with the project's infrastructure strategy.

.gitea/workflows/docker-build.yml

@@ -15,8 +15,7 @@ env:
 
 jobs:
   # Shared setup job for common steps
-  setup:
-    runs-on: ubuntu-latest
+  setup: self-hosted
     outputs:
       version: ${{ steps.meta.outputs.version }}
       labels: ${{ steps.meta.outputs.labels }}
@@ -45,7 +44,7 @@ jobs:
 
   # API Gateway build and push
   build-push-api-gateway:
-    runs-on: ubuntu-latest
+    runs-on: self-hosted
     needs: setup
     
     steps:
@@ -75,7 +74,7 @@ jobs:
 
   # Service Adapters build and push
   build-push-service-adapters:
-    runs-on: ubuntu-latest
+    runs-on: self-hosted
     needs: setup
     
     steps:
@@ -105,7 +104,7 @@ jobs:
 
   # API Docs build and push
   build-push-api-docs:
-    runs-on: ubuntu-latest
+    runs-on: self-hosted
     needs: setup
     
     steps:
@@ -135,7 +134,7 @@ jobs:
 
   # Frontend build and push
   build-push-frontend:
-    runs-on: ubuntu-latest
+    runs-on: self-hosted
     needs: setup
     
     steps: