Add kded6 source with pre-generated D-Bus XML and fix CMake prefix path

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

local/recipes/kde/kf6-kded6/source/.kde-ci.yml

@@ -0,0 +1,14 @@
+Dependencies:
+- 'on': ['Linux', 'FreeBSD', 'Windows']
+  'require':
+    'frameworks/extra-cmake-modules': '@same'
+    'frameworks/ki18n' : '@same'
+    'frameworks/kcoreaddons' : '@same'
+    'frameworks/kdbusaddons' : '@same'
+    'frameworks/kservice' : '@same'
+    'frameworks/kcrash' : '@same'
+    'frameworks/kdoctools' : '@same'
+
+Options:
+  test-before-installing: True
+  require-passing-tests-on: [ 'Linux', 'FreeBSD' ]