ci: Add firmware size check and version tag validation

- Fail build if binary exceeds 1920 KB partition
- Warn at 85% capacity
- Warn if git tag differs from embedded version

.gitea/workflows/lint.yml

@@ -54,6 +54,26 @@ jobs:
         run: |
           ls -lh get-started/csi_recv_router/build/*.bin
 
+      - name: Check firmware size
+        run: |
+          BIN="get-started/csi_recv_router/build/csi_recv_router.bin"
+          MAX_SIZE=1966080  # 0x1E0000 = 1920 KB partition
+          WARN_PERCENT=85
+
+          SIZE=$(stat -c%s "$BIN")
+          PERCENT=$((SIZE * 100 / MAX_SIZE))
+
+          echo "Firmware: $((SIZE/1024)) KB / $((MAX_SIZE/1024)) KB ($PERCENT%)"
+
+          if [ $SIZE -gt $MAX_SIZE ]; then
+            echo "::error::Firmware exceeds partition size!"
+            exit 1
+          fi
+
+          if [ $PERCENT -gt $WARN_PERCENT ]; then
+            echo "::warning::Firmware using $PERCENT% of partition"
+          fi
+
       - name: Upload firmware artifact
         run: |
           mkdir -p /tmp/artifacts
@@ -82,6 +102,20 @@ jobs:
         run: |
           cd workspace && . $HOME/esp/esp-idf/export.sh && cd get-started/csi_recv_router && idf.py build
 
+      - name: Validate version tag
+        working-directory: workspace
+        run: |
+          TAG="${{ github.ref_name }}"
+          # Extract version from binary metadata
+          BIN_VER=$(strings get-started/csi_recv_router/build/csi_recv_router.bin | grep -oP '^v\d+\.\d+(\.\d+)?' | head -1)
+
+          echo "Git tag: $TAG"
+          echo "Binary version: $BIN_VER"
+
+          if [ "$TAG" != "$BIN_VER" ]; then
+            echo "::warning::Tag ($TAG) differs from binary ($BIN_VER)"
+          fi
+
       - name: Create release and upload firmware
         env:
           GITEA_TOKEN: ${{ github.token }}