ci: add macOS/Windows PR check workflow

.github/workflows/pr-check-cross.yml

@@ -0,0 +1,52 @@
+name: PR Check (Cross-Platform)
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+jobs:
+  verify:
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5  # v4
+
+      - name: Setup Node
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020  # v4
+        with:
+          node-version: '20'
+          cache: 'npm'
+
+      - name: Install Node Dependencies
+        run: npm ci
+
+      - name: Setup Rust
+        uses: dtolnay/rust-toolchain@29eef336d9b2848a0b548edc03f92a220660cdb8  # stable
+        with:
+          components: clippy
+
+      - name: Clear stale sccache wrapper
+        shell: bash
+        run: unset RUSTC_WRAPPER 2>/dev/null; echo "RUSTC_WRAPPER=" >> "$GITHUB_ENV"
+
+      - name: Cache Rust
+        uses: swatinem/rust-cache@c19371144df3bb44fab255c43d04cbc2ab54d1c4  # v2.9.1
+        with:
+          workspaces: src-tauri
+          prefix-key: v1
+
+      - name: Rust Tests
+        shell: bash
+        run: cd src-tauri && cargo test
+
+      - name: Rust Clippy
+        shell: bash
+        run: cd src-tauri && cargo clippy -- -D warnings
+
+      - name: Frontend Build
+        run: npm run build

src-tauri/src/auth.rs

@@ -243,8 +243,8 @@ fn write_vault_windows(tmp_path: &std::path::Path, blob: &[u8]) -> Result<(), St
                     let stderr = String::from_utf8_lossy(&out.stderr);
                     log::warn!(
                         target: "auth::vault",
-                        code = ?out.status.code(),
-                        "icacls failed to tighten vault ACL; file may be world-readable: {stderr}"
+                        "icacls failed to tighten vault ACL (exit code {:?}); file may be world-readable: {stderr}",
+                        out.status.code(),
                     );
                 }
                 Err(e) => {

src-tauri/src/tests/flow_test.rs

@@ -333,7 +333,8 @@ fn pty_reader_pauses_without_acks_and_resumes_losslessly() {
 
     // ── Phase 2: 수신분을 ack하며 소비 → 재개되어 끝까지 유실 없이 도착해야 함
     flow.on_ack(CONN, &pty_id, received.len());
-    let deadline = std::time::Instant::now() + Duration::from_secs(60);
+    // macOS CI 러너 변동성 마진. 데이터 유실이라면 어떤 timeout도 fail이라 검증 강도는 유지된다.
+    let deadline = std::time::Instant::now() + Duration::from_secs(180);
     while !contains_subslice(&received, b"\r\n100000\r\n") {
         assert!(
             std::time::Instant::now() < deadline,