docs: document KF5 and KF6 support in README

README.md

@@ -24,12 +24,22 @@ are pure D-Bus clients — lightweight, stateless, and independently restartable
 ## Dependencies
 
 - Go 1.25+
-- Qt 6 (Core, DBus, Widgets, Quick)
+- Qt 6 (Core, DBus, Widgets, Quick) or Qt 5 (Core, DBus, Widgets, Quick, Qml)
 - KDE Frameworks 6 (StatusNotifierItem, Runner, TextEditor, CoreAddons, Config)
-- Plasma 6 (for Plasmoid)
+  or KDE Frameworks 5 (Notifications, Runner, TextEditor, CoreAddons, Config, Plasma)
+- Plasma 6 or Plasma 5 (for Plasmoid)
 - ECM (Extra CMake Modules)
 - ollie/core (sibling directory at `../ollie/core`)
 
+KF6/Qt6 is the default (`CMakeLists.txt`). To build against KF5/Qt5, point CMake
+at the alternate file:
+
+```sh
+cmake -S . -B build-cmake -DCMAKE_PROJECT_INCLUDE=CMakeLists-kf5.txt
+# or copy/symlink it:
+ln -sf CMakeLists-kf5.txt CMakeLists.txt
+```
+
 ## Build
 
 ```sh
@@ -40,8 +50,8 @@ Outputs:
 - `build/libollie.so` — Go shared library (cgo c-shared)
 - `build-cmake/ollie-kde` — D-Bus daemon
 - `build-cmake/ollie-tray` — system tray icon
-- `build-cmake/lib/kf6/krunner/krunner_ollie.so` — KRunner plugin
-- `build-cmake/lib/kf6/ktexteditor/ollie_kate.so` — Kate plugin
+- `build-cmake/lib/kf6/krunner/krunner_ollie.so` — KRunner plugin (kf5/ on KF5 builds)
+- `build-cmake/lib/kf6/ktexteditor/ollie_kate.so` — Kate plugin (kf5/ on KF5 builds)
 - `build-cmake/org/ollie/private/` — Plasmoid QML plugin
 
 ## Install
@@ -51,7 +61,7 @@ Outputs:
 sudo install -m755 build-cmake/ollie-kde /usr/bin/
 sudo install -m755 build/libollie.so /usr/lib64/
 
-# KRunner plugin
+# KRunner plugin (use kf5/ and qt5 paths on KF5 builds)
 sudo cp build-cmake/lib/kf6/krunner/krunner_ollie.so /usr/lib64/qt6/plugins/kf6/krunner/
 
 # Kate plugin