Add DNS first-seen and last-seen history

[JeremyZeng77]

Summary

• adds first-seen, last-seen, and seen metadata to DNS records in JSON output
• preserves records that disappeared from the latest scan so rotating/load-balanced answers keep their historical last-seen value
• adds --fs, --ls <days>, and --lsd <MM/DD/YYYY> reporting flags for first-seen and stale last-seen records
• documents the history fields and reporting flags in the README

Fixes #1.

Verification

• git diff --check
• WSL/Ubuntu single-translation-unit compile checks:
  • g++ -std=c++17 -Iinclude -ICLI11/include -Ijson/single_include -Ispdlog/include -c source/cli_preprocessor.cpp -o /tmp/dooked_cli_preprocessor.o
  • g++ -std=c++17 -Iinclude -ICLI11/include -Ijson/single_include -Ispdlog/include -c source/main.cpp -o /tmp/dooked_main.o
  • g++ -std=c++17 -Iinclude -ICLI11/include -Ijson/single_include -Ispdlog/include -c source/utils/io_utils.cpp -o /tmp/dooked_io_utils.o

I also attempted a full CMake build in Ubuntu 24.04; it reaches existing Boost 1.83 compatibility errors in unrelated files before completing.

Bounty payout

If this is selected for the $100 bounty, PayPal payout can be sent to: https://paypal.me/Jeremytsangchina