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/build.gradle.kts

@@ -8,7 +8,7 @@ val artefactVersion: String by project
 val buildChannel: String by project
 val vendor: String by project
 
-group = "com.onixbyte.helix"
+group = "com.onixbyte.ahsarahguide"
 version = artefactVersion
 
 tasks.withType<JavaCompile> {