Fix Forgejo CI workflows and add .gitkeep files

- Fix rsync exclusions to properly preserve accounts, cache, and sessions
- Remove tiles exclusion (not used in this project)
- Add .gitkeep files to track empty directories structure
- Update .gitignore to allow .gitkeep files

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

.gitignore

@@ -62,18 +62,21 @@ public/.idea
 
 public/site/cache/*
 !public/site/cache/index.html
+!public/site/cache/.gitkeep
 
 # Accounts
 # ---------------
 
 public/site/accounts/*
 !public/site/accounts/index.html
+!public/site/accounts/.gitkeep
 
 # Sessions
 # ---------------
 
 public/site/sessions/*
 !public/site/sessions/index.html
+!public/site/sessions/.gitkeep
 
 # License
 # ---------------