Request capture pixels from the selection screen's backing scale

SCDisplay.width is in points, not pixels: the previous fix sent point
counts to SCStreamConfiguration, producing blurry main-screen captures and
failed secondary-screen captures. Multiply by the backing scale factor of
the screen containing the selection (defaulting to 1x, never forcing 2x).

💘 Generated with Crush

Assisted-by: Crush:deepseek-v4-flash-0731

build-app.sh

@@ -108,9 +108,9 @@ cat > "$APP/Contents/Info.plist" <<'PLIST'
     <key>CFBundleIconFile</key>
     <string>Icon</string>
     <key>CFBundleShortVersionString</key>
-    <string>1.1.4</string>
+    <string>1.1.5</string>
     <key>CFBundleVersion</key>
-    <string>14</string>
+    <string>15</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>