feat: Central via the in-cluster Maven proxy; -T1C builds

maven.kof22.com caches Central (one download per artifact, no 429s);
-T1C uses one thread per runner core instead of a fixed 4.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitea/workflows/container.yaml

@@ -94,7 +94,7 @@ jobs:
           cat > /tmp/mvn-settings.xml <<'EOF'
           <settings>
             <mirrors>
-              <mirror><id>google-maven-central</id><mirrorOf>central</mirrorOf><url>https://maven-central.storage-download.googleapis.com/maven2/</url></mirror>
+              <mirror><id>kof22-maven-proxy</id><mirrorOf>central</mirrorOf><url>https://maven.kof22.com/maven2/</url></mirror>
             </mirrors>
             <servers>
               <server><id>qrun-packages</id><username>${env.GITHUB_ACTOR}</username><password>${env.PACKAGES_TOKEN}</password></server>

.gitea/workflows/maven.yaml

@@ -115,9 +115,9 @@ jobs:
         run: |
           cat > /tmp/mvn-settings.xml <<'EOF'
           <settings>
-            <!-- repo.maven.apache.org rate-limits (429) this network; Google's official Central mirror does not. -->
+            <!-- Central through the in-cluster caching proxy (maven.kof22.com): one download per artifact, no 429s. -->
             <mirrors>
-              <mirror><id>google-maven-central</id><mirrorOf>central</mirrorOf><url>https://maven-central.storage-download.googleapis.com/maven2/</url></mirror>
+              <mirror><id>kof22-maven-proxy</id><mirrorOf>central</mirrorOf><url>https://maven.kof22.com/maven2/</url></mirror>
             </mirrors>
             <servers>
               <server><id>gitea</id><username>${env.GITHUB_ACTOR}</username><password>${env.PACKAGES_TOKEN}</password></server>
@@ -169,7 +169,7 @@ jobs:
 
       - name: Verify
         if: steps.plan.outputs.kind == 'verify'
-        run: mvn -T4 verify
+        run: mvn -T1C verify
 
       - name: Calculate version
         if: steps.plan.outputs.kind == 'publish'
@@ -242,7 +242,7 @@ jobs:
         if: steps.plan.outputs.kind == 'publish'
         env:
           OWNER: ${{ github.repository_owner }}
-        run: mvn -T4 deploy -DaltDeploymentRepository=gitea::https://git.kof22.com/api/packages/${OWNER}/maven
+        run: mvn -T1C deploy -DaltDeploymentRepository=gitea::https://git.kof22.com/api/packages/${OWNER}/maven
 
       - name: Commit version back
         if: steps.plan.outputs.kind == 'publish' && steps.version.outputs.push_branch != ''