Terminate stale Kapture instances at launch; log topmost windows

A stale copy surviving an update keeps its own hotkey and overlays on
screen, silently eating every click meant for the new instance (matching
the empty session logs). New copies now force-terminate older instances,
and the first window scan logs the topmost on-screen windows so anything
covering the overlays is visible in diagnostics.

💘 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>1.6.4</string>
+    <string>1.6.5</string>
     <key>CFBundleVersion</key>
-    <string>64</string>
+    <string>65</string>
     <key>LSUIElement</key>
     <true/>
     <key>NSHighResolutionCapable</key>