refactor: rename delta-force-guide to ahsarah-guide and merge into monorepo

- Merge delta-force-guide-server into server/ subdirectory
- Merge delta-force-guide-web into web/ subdirectory
- Rename Java package com.onixbyte.deltaforceguide to com.onixbyte.ahsarahguide
- Rename DeltaForceGuideApplication to AhsarahGuideApplication
- Update all config files, Dockerfiles, and CI workflows
- Update frontend display name and repo links
- Update legal documents (EULA, PrivacyPolicy)
- Create root-level CLAUDE.md, README.md, LICENCE, .gitignore, .gitattributes
- Move CI workflows to root .gitea/workflows/ with working-directory
- Delete .gitlab-ci.yml (legacy)
- Preserve git history from both original repositories

server/config/application-prod.yaml.example

@@ -95,7 +95,7 @@ app:
     max-age: PT2H
   jwt:
     # Issuer identifier, domain name is recommended.
-    issuer: dfguide.local
+    issuer: ahsarah-guide.local
 
     # Token signing secret, a 32-byte long or longer string is recommended.
     secret: qwertyuiopasdfghjklzxcvbnm123456