The review asked for a regression test pinning DTD-prohibited parsing. Writing
it showed the premise was wrong: XDocument.Parse permits an internal DTD subset
and expands its entities, so a DOCTYPE-bearing response body parsed fine and the
guard did not exist (entity-expansion DoS on external input).
Parse now goes through XmlReader with DtdProcessing.Prohibit and a null
XmlResolver. The regression test feeds a DOCTYPE + ENTITY payload shaped as a
well-formed EWS error response, so it fails if DtdProcessing is ever loosened
rather than passing for the unrelated-XML reason.
Remove project bookkeeping citations from shipped code comments across the
solution: hyphenated task IDs (WP-14, StoreAndForward-025), milestone/task/
issue refs (M3, Task 4, Audit Log #23, #21), Bundle X task-bundle labels,
and C/D/K/S/T phase labels.
Comment text only — no code logic, string/log literals, or XML-doc structure
changed. Genuine descriptions are preserved (only the citation is stripped),
and technical lookalikes are retained (UTF-8, SHA-256, T00:00:00, M365,
UTC-5, pre-C4/pre-C5 schema versions). Flagged by the new CommentChecker
TaskReferenceInComment / TrackingReferenceInComment checks plus targeted
grep passes; full solution builds clean, append-only guard tests pass.
Resolve all 622 issues flagged by the enhanced CommentChecker: add missing
<returns> tags (incl. the standard phrasing on non-generic Task methods),
add missing <summary> tags, and replace misused/redundant <inheritdoc/> on
members that override or implement nothing with real documentation.
Documentation-only — no behavior change; solution builds clean.
Joseph Doherty