style: normalize formatting and semantic ordering across all QSS themes

[GTRONICK]

• Convert all rgb() color values to hex equivalents
• Remove duplicate properties within selectors (keep last declaration)
• Add missing semicolons to property declarations
• Normalize indentation to single tab per property across all files
• Enforce one space between selector and opening brace
• Ensure one blank line between rule blocks
• Add two blank lines between header comment and first rule
• Expand comma-separated multi-selector lines to one selector per line
• Sort rule blocks semantically: general selectors before specific ones (fewer sub-controls/pseudo-states first)
• Sort selectors within multi-selector groups by the same criteria
• Remove blank lines immediately after opening braces
• Add Last updated timestamp header to all files