docs: add save state incompatibility warning and backup guidance Updates Home, Migrating-from-OpenEmu, and Save-States pages to document the new warning dialog from PR #152 and encourage users to back up saves. Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
Initial wiki: 12 pages covering getting started, BIOS, importing, CD games, controllers, troubleshooting, and more