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.

pkg/utils/string.go

@@ -0,0 +1,12 @@
+package utils
+
+import "strings"
+
+// TrimStringFields trims leading and trailing spaces from all provided string pointers.
+func TrimStringFields(fields ...*string) {
+	for _, f := range fields {
+		if f != nil {
+			*f = strings.TrimSpace(*f)
+		}
+	}
+}