[tintinhamans]

Merge after #653.

Archive priority was an accident of file names, and the core pack and community patch were hard coded. Every archive now has an explicit priority, and data_packs in settings.json has three layers: user, generals_online and community_patch. From the top the lookup is loose files in the game folder, -mod / -modDir, non-retail BIGs in the game folders, user, generals_online, community_patch, then retail.

"data_packs": {
  "user": { "enabled": true, "include_paths": [], "exclude_paths": [] },
  "generals_online": { "enabled": true, "include_paths": ["user:GeneralsOnlineGameData/GeneralsOnline_Core.big"] },
  "community_patch": { "enabled": true, "include_paths": ["user:GeneralsOnlineGameData/500_900_CommunityPatch_CoreINI.big"] }
}

include_paths entries are BIGs, folders of BIGs or *.big patterns (game:, user: or absolute), mounted in list order with the first one winning. exclude_paths exists on user only. It hides loose files and BIGs of the game folders, never the retail archives. A missing or invalid field keeps its default, and invalid entries are dropped and logged.

use_community_data_patch is read once as community_patch.enabled and dropped on save. -disableCommunityDataPatch turns the community_patch layer off for that launch only. Settings now load before the archives mount. The Generals data is mounted once, where Steam installs used to mount it twice, and ranks below the Zero Hour archives. scripts/pack_go_data.py builds the core BIG.

CRC handling is untouched. Deployment: the updater ships GeneralsOnline_Core.big to <user data>\GeneralsOnlineGameData\, and the Launcher's community patch checkbox should write data_packs.community_patch.enabled (the old key is still migrated).