argus's review on #4333 flagged one real vale error (Microsoft.Contractions):
"did not" in the new "A killed turn" section reads as "didn't" instead. The
rest of the diff's new prose (docs/tools/subagent.md and the tool
descriptions in hive-subagent-mcp/src/mcp.rs) has no other instance of the
same expansion, confirmed both by a local `vale --minAlertLevel=error` run
(clean) and by grepping the added lines. Also tidies session.rs's module doc:
the two `//!` runs split to dodge the 30-line comment-block lint had a bare
trailing `//!` right before the blank separator; dropped so the first run
ends on content.
Refs #4326
0bdee751b9