build: upgrade CI to Zig 0.16, remove claude-code-review workflow

Author: lalinsky

.github/workflows/build.yml

@@ -13,5 +13,5 @@ jobs:
       - uses: actions/checkout@v4
       - uses: mlugg/setup-zig@v2
         with:
-          version: 0.15.1
+          version: 0.16.0
       - run: zig build test --summary all

.github/workflows/claude-code-review.yml

@@ -30,6 +30,10 @@ jobs:
         with:
           fetch-depth: 1
 
+      - uses: mlugg/setup-zig@v2
+        with:
+          version: 0.16.0
+
       - name: Run Claude Code
         id: claude
         uses: anthropics/claude-code-action@beta