fix: resolve desktop menu launcher issue and improve icon handling

- Install application properly with pip install -e . to create executable
- Fix desktop file icon reference to use base name instead of absolute path
- Update all installation scripts to use Icon=bash-script-maker for better desktop environment compatibility
- Ensure proper desktop integration works across different Linux distributions
- Fix 'Programm ist nicht auffindbar' error when launching from start menu

Author: marci

install.sh

@@ -304,7 +304,7 @@ if main_installation; then
 Name=Bash-Script-Maker
 Comment=Ein GUI-Programm zur Erstellung von Bash-Scripts
 Exec=$HOME/.local/bin/bash-script-maker
-Icon=$HOME/.local/share/icons/hicolor/scalable/apps/bash-script-maker.svg
+Icon=bash-script-maker
 Terminal=false
 Type=Application
 Categories=Development;Utility;TextEditor;

install_apt.sh

@@ -170,7 +170,7 @@ if [ -f "bash-script-maker.desktop" ] && [ -f "assets/bash-script-maker.svg" ];
 Name=Bash-Script-Maker
 Comment=Ein GUI-Programm zur Erstellung von Bash-Scripts
 Exec=$HOME/.local/bin/bash-script-maker
-Icon=$HOME/.local/share/icons/hicolor/scalable/apps/bash-script-maker.svg
+Icon=bash-script-maker
 Terminal=false
 Type=Application
 Categories=Development;Utility;TextEditor;

install_desktop_integration.sh

@@ -49,7 +49,7 @@ if cat > ~/.local/share/applications/bash-script-maker.desktop << EOF
 Name=Bash-Script-Maker
 Comment=Ein GUI-Programm zur Erstellung von Bash-Scripts
 Exec=$HOME/.local/bin/bash-script-maker
-Icon=$HOME/.local/share/icons/hicolor/scalable/apps/bash-script-maker.svg
+Icon=bash-script-maker
 Terminal=false
 Type=Application
 Categories=Development;Utility;TextEditor;

install_dnf.sh

@@ -163,7 +163,7 @@ if [ -f "bash-script-maker.desktop" ] && [ -f "assets/bash-script-maker.svg" ];
 Name=Bash-Script-Maker
 Comment=Ein GUI-Programm zur Erstellung von Bash-Scripts
 Exec=$HOME/.local/bin/bash-script-maker
-Icon=$HOME/.local/share/icons/hicolor/scalable/apps/bash-script-maker.svg
+Icon=bash-script-maker
 Terminal=false
 Type=Application
 Categories=Development;Utility;TextEditor;