refactor: Standardize theme structure and update configs

- Restructured 'minimal' theme to use 'static/css' and 'static/js' subdirectories for assets, aligning with qsgen3's expected theme structure.
- Moved 'minimaltemplate-v1.css' to 'themes/minimal/static/css/'.
- Moved JS files from 'themes/minimal/css/' to 'themes/minimal/static/js/'.
- Updated 'site.conf.example' to reflect 'minimal' theme usage and correct 'site_theme_css_file' path relative to the theme's static directory.
- Cleaned up redundant CSS variable definitions in 'bin/qsgen3' (_generate_index_page function).

bin/qsgen3

@@ -519,12 +519,6 @@ _generate_index_page() {
     _log DEBUG "Successfully wrote comprehensive YAML to $temp_yaml_file"
 
 
-    # Theme CSS handling for index page
-    local source_theme_css_file="${QSG_CONFIG[paths_layouts_dir]}/css/${QSG_CONFIG[site_theme]}.css"
-    local target_theme_css_dir="${QSG_CONFIG[paths_output_dir]}/css"
-    local target_theme_css_file="$target_theme_css_dir/theme.css"
-    local pandoc_css_path_for_index="/css/theme.css"
-
     _log DEBUG "In _generate_index_page: PROJECT_ROOT='$PROJECT_ROOT'"
     local pandoc_cmd_index=(
         pandoc
@@ -550,7 +544,7 @@ _generate_index_page() {
 
     _log DEBUG "Pandoc command for index page will be constructed as follows:"
     _log DEBUG "Base command: pandoc"
-    _log DEBUG "CSS arg if theme applies: --css ${pandoc_css_path_for_index}"
+    _log DEBUG "CSS arg if theme applies: --css ${QSG_CONFIG[pandoc_css_path_arg]:-(not set or expected CSS file not found in output)}"
     _log DEBUG "Metadata file arg: --metadata-file ${temp_yaml_file}"
     _log DEBUG "Template arg: --template=${layout_index_file}"
     _log DEBUG "Output arg: --output=${output_index_file}"

site.conf.example

@@ -5,7 +5,8 @@
 site_name="My Example Site"
 site_tagline="An example site generated by qsgen3"
 site_url="http://localhost:8000" # Or your actual production URL
-site_theme="default" # Specifies the theme to use (e.g., default, dark)
+site_theme="minimal" # Specifies the theme to use (e.g., minimal, default)
+site_theme_css_file="css/minimaltemplate-v1.css" # Path to main CSS file, relative to THEME'S static/ directory
 
 # --- Paths (relative to project root) ---
 paths_content_dir="content"