ci: go vet + go test 추가 + Go 1.25 업그레이드 + 태그 릴리즈 빌드

- test job: go vet + build + go test ./... (Windows runner)
- release job: 'v*' 태그 push 시 launcher.exe를 GitHub Release에 업로드
- Go 1.24 → 1.25 업그레이드

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

.github/workflows/ci.yml

@@ -1,21 +1,56 @@
-name: CI
+name: CI/CD
 
 on:
   push:
     branches: [main]
+    tags: ['v*']
   pull_request:
     branches: [main]
 
 jobs:
-  build:
+  # ── 1. 정적 분석 + 빌드 + 테스트 ──────────────────────────────────────────
-    # Windows runner required for Win32 API dependencies
+  test:
+    # Win32 API 의존성으로 Windows runner 필수
     runs-on: windows-latest
     steps:
       - uses: actions/checkout@v4
 
       - uses: actions/setup-go@v5
         with:
-          go-version: '1.24'
+          go-version: '1.25'
+          cache: true
+
+      - name: Vet
+        run: go vet ./...
 
       - name: Build
         run: go build -ldflags="-H windowsgui -s -w" -o launcher.exe .
+
+      - name: Test
+        run: go test ./... -v
+
+  # ── 2. 릴리즈 빌드 & GitHub Release 업로드 (태그 push 시만) ───────────────
+  release:
+    needs: test
+    if: startsWith(github.ref, 'refs/tags/v')
+    runs-on: windows-latest
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-go@v5
+        with:
+          go-version: '1.25'
+          cache: true
+
+      - name: Build release binary
+        run: |
+          $VERSION = "${{ github.ref_name }}"
+          go build -ldflags="-H windowsgui -s -w -X main.version=$VERSION" -o launcher.exe .
+
+      - name: Create GitHub Release
+        uses: softprops/action-gh-release@v2
+        with:
+          files: launcher.exe
+          generate_release_notes: true