fix: 更新所有CI workflow的Go版本验证至1.25.6

.github/workflows/backend-ci.yml

@@ -19,7 +19,7 @@ jobs:
           cache: true
       - name: Verify Go version
         run: |
-          go version | grep -q 'go1.25.5'
+          go version | grep -q 'go1.25.6'
       - name: Unit tests
         working-directory: backend
         run: make test-unit
@@ -38,7 +38,7 @@ jobs:
           cache: true
       - name: Verify Go version
         run: |
-          go version | grep -q 'go1.25.5'
+          go version | grep -q 'go1.25.6'
       - name: golangci-lint
         uses: golangci/golangci-lint-action@v9
         with:

.github/workflows/release.yml

@@ -115,7 +115,7 @@ jobs:
 
       - name: Verify Go version
         run: |
-          go version | grep -q 'go1.25.5'
+          go version | grep -q 'go1.25.6'
 
       # Docker setup for GoReleaser
       - name: Set up QEMU