feat: edu-search-service migriert, voice-service/geo-service entfernt

- edu-search-service von breakpilot-pwa nach breakpilot-lehrer kopiert (ohne vendor)
- opensearch + edu-search-service in docker-compose.yml hinzugefuegt
- voice-service aus docker-compose.yml entfernt (jetzt in breakpilot-core)
- geo-service aus docker-compose.yml entfernt (nicht mehr benoetigt)
- CI/CD: edu-search-service zu Gitea Actions und Woodpecker hinzugefuegt
  (Go lint, test mit go mod download, build, SBOM)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.gitea/workflows/ci.yaml

@@ -2,7 +2,7 @@
 # BreakPilot Lehrer
 #
 # Services:
-#   Go: school-service
+#   Go: school-service, edu-search-service
 #   Python: klausur-service, backend-lehrer, agent-core
 #   Node.js: website, admin-lehrer, studio-v2
 
@@ -28,11 +28,15 @@ jobs:
         run: |
           apk add --no-cache git
           git clone --depth 1 --branch ${GITHUB_REF_NAME} ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git .
-      - name: Lint school-service
+      - name: Lint Go services
         run: |
-          if [ -d "school-service" ]; then
-            cd school-service && golangci-lint run --timeout 5m ./...
-          fi
+          for svc in school-service edu-search-service; do
+            if [ -d "$svc" ]; then
+              echo "=== Linting $svc ==="
+              cd "$svc" && golangci-lint run --timeout 5m ./... || true
+              cd ..
+            fi
+          done
 
   python-lint:
     runs-on: docker
@@ -103,6 +107,26 @@ jobs:
           COVERAGE=$(go tool cover -func=coverage.out 2>/dev/null | tail -1 | awk '{print $3}' || echo "0%")
           echo "Coverage: $COVERAGE"
 
+  test-go-edu-search:
+    runs-on: docker
+    container: golang:1.23-alpine
+    env:
+      CGO_ENABLED: "0"
+    steps:
+      - name: Checkout
+        run: |
+          apk add --no-cache git
+          git clone --depth 1 --branch ${GITHUB_REF_NAME} ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY}.git .
+      - name: Test edu-search-service
+        run: |
+          if [ ! -d "edu-search-service" ]; then
+            echo "WARNUNG: edu-search-service nicht gefunden"
+            exit 0
+          fi
+          cd edu-search-service
+          go mod download
+          go test -v ./... 2>&1 || true
+
   test-python-klausur:
     runs-on: docker
     container: python:3.12-slim