Fix talkkonnect permission issues and add setup documentation

The installation script had a critical bug where it created the config
directory in the script runner's home directory instead of the target
user's home directory. This caused "permission denied" errors when the
systemd service tried to run as the target user.

Changes:
- Fixed CONFIG_DIR to use $TARGET_HOME instead of $HOME
- Updated config path replacements to use $TARGET_HOME
- Added ownership change after config creation when running as different user
- Created fix_talkkonnect_permissions.sh script to repair existing installations
- Added comprehensive TALKKONNECT_SETUP.md with troubleshooting guide

This fixes the "open /home/user/.config/talkkonnect/talkkonnect.xml: permission denied" error.

talkkonnect_complete_install.sh

@@ -434,7 +434,7 @@ echo "======================================================================="
 echo "[+] CREATING CONFIGURATION"
 echo "======================================================================="
 
-CONFIG_DIR="$HOME/.config/talkkonnect"
+CONFIG_DIR="$TARGET_HOME/.config/talkkonnect"
 mkdir -p "$CONFIG_DIR"
 
 cat > "$CONFIG_DIR/talkkonnect.xml" << 'EOFXML'
@@ -523,7 +523,13 @@ cat > "$CONFIG_DIR/talkkonnect.xml" << 'EOFXML'
 EOFXML
 
 # Update the log path to use actual username
-sed -i "s|/home/user/|$HOME/|g" "$CONFIG_DIR/talkkonnect.xml"
+sed -i "s|/home/user/|$TARGET_HOME/|g" "$CONFIG_DIR/talkkonnect.xml"
+
+# Set proper ownership if running as a different user
+if [ "$TARGET_USER" != "$USER" ]; then
+    sudo chown -R "$TARGET_USER:$TARGET_USER" "$CONFIG_DIR"
+    echo "[+] Set ownership of config directory to $TARGET_USER"
+fi
 
 echo "[+] Created configuration file: $CONFIG_DIR/talkkonnect.xml"