Document DNS Query Options (constructor + getters/setters) in usage docs

[Copilot]

The user documentation lacked coverage of DNSQuery construction options (port, timeout, UDP/TCP, debug flags) and their corresponding getters/setters.

Changes

• docs/usage.md: added a new "DNS Query Options" section covering:
  • Full constructor signature with default values (port=53, timeout=60, udp=true, debug=false, binarydebug=false)
  • Getter/setter pairs for server, port, timeout, udp, debug, binarydebug
  • connectionException/responseException getter/setter pair (default false), cross-referenced to the existing "Error Handling" section
• docs/ folder: brought the full GitHub Pages docs tree (unchanged apart from usage.md) onto this branch, since it previously only existed on the website branch and this branch's history is unrelated to it.

Example

$query = new DNSQuery("some.server.com", 5353, 10, false); // TCP, port 5353, 10s timeout

// or change after construction
$query = new DNSQuery("some.server.com");
$query->setPort(5353);
$query->setUdp(false);

Note: docs/ is normally maintained on the separate website branch (unrelated git history, used for GitHub Pages). This PR targets copilot/update-website-branch-docs instead, so the docs/ content will need to be merged/cherry-picked into website separately.