Moves the 11 Fixed issues (#001-006, #008-012) into issues/_archive_/,
which is gitignored — they stay on local disk and in git history but drop
out of the committed tree, keeping the issues/ dir focused on what's open.
The sibling test project reads this dir by local path, so it still sees
the archived files. Adds the three new open issues found in round-3
testing: #014 (stored XSS in markdown/deck/html_fragment — High), #015
(RecursionError -> 500 on deeply nested JSON), #016 (ragged CSV rows lose
data in the rendered table). Documents the archive convention in the README.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
