Dolphin Serial ⇒ Candidate Timestamps

This tool enumerates possible timestamps for both Dolphin serial generators:

• Legacy: fmt::format("{%j%H%M%S}", localtime(t)) → day‑of‑year + HHMMSS (9 digits)
• Current: fmt::format("{:09}", t % 1 000 000 000) → last 9 digits of Unix time (wraps every ≈31 years 8 months)