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/lib/app-info.ts

@@ -0,0 +1,6 @@
+import packageJson from "../package.json"
+
+const rawVersion = process.env.NEXT_PUBLIC_APP_VERSION || packageJson.version
+
+export const APP_VERSION = rawVersion.startsWith('v') ? rawVersion.slice(1) : rawVersion
+export const APP_BUILD_DATE = process.env.NEXT_PUBLIC_APP_BUILD_DATE || ""