Important plugin update.

1. PlaceholderAPI integration and expansion

• Added many %valentines_*% placeholders for:
  • player stats (received/given/total)
  • relationship/marriage/engagement values
  • achievements/progress
  • leaderboard values
• Details can be found with /valentines placeholders or description page

2. New player stats command

• Added /valentinesplayer (aliases: vplayer, lovestats, vst) to view a player's Valentines stats in chat

3. GUI improvements

• Added/changed to player heads in some GUIs

4. Proposal/engagement data improvements

• In-code optimization

5. Version checker and version command

• Remade Github-based version checker that checks this page:
  • https://github.com/Primly-Project/Valentines/releases for newer versions
• Added /vver command (aliases: valver, vversion) with permission valentines.version
• /vver displays:
  • current version
  • latest detected version
  • last check timestamp
  • update status
• /vver check now:
  • checks if new version is available
• Added version checker config options:
  • version-checker.enabled
  • version-checker.check-on-startup
  • version-checker.minimum-interval-seconds
• Added console output for version status (current/latest/update availability)

6. Metadata and language updates

• Added/updated language keys in lang/en.yml for:
  • placeholders help
  • version command outputs and check statuses