Fix dnf upgrade --allowerasing errors with EPEL packages

Fix 4 errors that occurred when running dnf upgrade --allowerasing on a
system with EPEL KDE packages installed:

1. plasma-discover: Fix typo "sonic-desktop-interface)" -> "sonic-desktop-interface"
   in Requires (stray closing parenthesis in spec)

2. sonic-frameworks-sso: Remove Obsoletes for signon and signon-qt6.
   The SonicDE SSO package provides libsignon-qt6.so.0 while the EPEL
   signon-qt6 provides libsignon-qt6.so.1. Obsoleting signon-qt6 breaks
   accounts-qml-module-qt6 and signon-plugin-oauth2 which need .so.1.
   Both packages can coexist since they install different .so versions.

3. sonic-terminal-tools: Change kdesu dependency from strict version
   match (= 1:6.7.4-3) to >= 1:6.7.4 so it works with any kdesu 6.7.4
   release. Also add Obsoletes for kdesu < 1:6.7.4-2.el10 in the kdesu
   subpackage so it properly replaces the old EPEL kdesu from kde-cli-tools.

4. kamera: Add kamera package with Requires changed from kde-cli-tools
   to sonic-terminal-tools. The EPEL kamera requires kde-cli-tools which
   is obsoleted by sonic-terminal-tools, causing a circular dependency
   resolution failure.

5. skanpage: Change Requires from kquickimageeditor-qt6 (obsoleted by
   sonic-quick-image-editor-qt6) to sonic-quick-image-editor-qt6.

Result: dnf upgrade --allowerasing --best from standard EPEL KDE now
completes with 0 errors and 0 package removals.

Generated with [Devin](https://devin.ai)

Co-Authored-By: Devin <158243242+devin-ai-integration[bot]@users.noreply.github.com>

skanpage/skanpage.spec

@@ -1,6 +1,6 @@
 Name:     skanpage
 Version:        26.04.3
-Release:        1%{?dist}
+Release:        2%{?dist}
 Summary:  Utility to scan images and multi-page documents
 License:  BSD-2-Clause AND BSD-3-Clause AND CC0-1.0 AND GPL-2.0-only AND GPL-3.0-only
 
@@ -50,7 +50,7 @@ BuildRequires:  cmake(Leptonica)
 
 Requires: qt6-qtquickcontrols2
 Requires:      sonic-frameworks-quick-ui
-Requires: kquickimageeditor-qt6
+Requires: sonic-quick-image-editor-qt6
 
 Recommends: sane-backends-drivers-scanners