Fix CI: remove unused variable warning, add shallow clone

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: unamedkr

.github/workflows/ci.yml

@@ -25,6 +25,12 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+
+      - name: Install dependencies (Ubuntu)
+        if: runner.os == 'Linux'
+        run: sudo apt-get update && sudo apt-get install -y cmake
 
       - name: Configure CMake
         run: >

src/engine/tq_ops.c

@@ -724,7 +724,6 @@ static int      g_q8_cap = 0;
 void tq_matmul_q4(float* out, const float* x, const uint8_t* w_qs, const float* w_scales,
                    int n, int d) {
     /* Quantize activation x to Q8 (amortized across all rows) */
-    int n_blocks = d / 32;
     if (d > g_q8_cap) {
         free(g_q8_buf); free(g_q8_scales);
         g_q8_buf = (int8_t*)malloc((size_t)d * sizeof(int8_t));