fix(ci): ensure Linux electron binary, pass electronDist per-platform

electron-nightly may not auto-download the Linux binary on CI.
Add explicit step to trigger download if missing. Pass electronDist
as CLI override per-platform (dist-win for Windows, dist for Linux)
instead of in config. Write path.txt on all platforms like KPC.

.github/workflows/build-release.yml

@@ -56,18 +56,22 @@ jobs:
         if: steps.version-check.outputs.SKIP == 'false'
         run: npm ci --legacy-peer-deps
 
+      - name: Ensure Electron Linux binary
+        if: steps.version-check.outputs.SKIP == 'false'
+        run: |
+          if [ ! -f node_modules/electron/dist/electron ]; then
+            echo "Electron Linux binary not found in dist/, triggering download..."
+            node node_modules/electron/install.js
+          fi
+          echo "=== Electron binaries ==="
+          echo "dist/electron: $(ls -lh node_modules/electron/dist/electron 2>/dev/null || echo MISSING)"
+          echo "dist-win/electron.exe: $(ls -lh node_modules/electron/dist-win/electron.exe 2>/dev/null || echo MISSING)"
+          echo "path.txt: $(cat node_modules/electron/path.txt 2>/dev/null || echo MISSING)"
+
       - name: Build source
         if: steps.version-check.outputs.SKIP == 'false'
         run: npm run build
 
-      - name: Verify Electron binaries
-        if: steps.version-check.outputs.SKIP == 'false'
-        run: |
-          echo "=== Electron dist (stock, for Linux build) ==="
-          ls node_modules/electron/dist/electron 2>/dev/null && echo "OK" || echo "MISSING"
-          echo "=== Electron dist-win (patched, for Windows build) ==="
-          ls node_modules/electron/dist-win/electron.exe 2>/dev/null && echo "OK" || echo "MISSING"
-
       - name: Build Windows distributables
         if: steps.version-check.outputs.SKIP == 'false'
         env:
@@ -76,7 +80,7 @@ jobs:
 
       - name: Build Linux distributables
         if: steps.version-check.outputs.SKIP == 'false'
-        run: npx electron-builder --linux --publish never
+        run: npx electron-builder --linux -c.electronDist=node_modules/electron/dist --publish never
 
       - name: Report build sizes
         if: steps.version-check.outputs.SKIP == 'false'