refactor(repo): consolidate openflare-server to root and move subprojects to internal/apps

- Merge all files inside openflare-server to the repository root directory.
- Relocate agent, relay, and flared subprojects from internal/ to internal/apps/.
- Combine docker-compose files and update build context paths to root.
- Update GitHub workflows and Dockerfiles to refer to new directories and package names.
- Rewrite Go package imports across all files.
- Resolve database renew test race condition and clean up docs.

frontend/app/(main)/settings/security/page.tsx

@@ -0,0 +1,5 @@
+import {redirect} from "next/navigation"
+
+export default function SecurityPage() {
+  redirect("/admin/settings")
+}