workflow: drop docs/WhatsNew.md (Notify carries done-state on its own)

WhatsNew.md duplicated the Notify text into a file the only reader
(the user) does not consult. Removed the file and trimmed every
reference in the live control docs (CLAUDE.md, skills/boss,
skills/implement). The editorial rules (no internals,
telegram-pragmatic, factual) are preserved in skills/boss as
notify-text discipline. Historical specs/plans/journals are not
rewritten — they show the contemporaneous state.

CLAUDE.md

@@ -242,15 +242,6 @@ Existing entries are not retroactively renamed.
   bite-sized executable plan produced by `skills/planner`, consumed
   by `skills/implement`.
 
-- **`docs/WhatsNew.md`** (since 2026-05-11): the user-facing
-  changelog, written for the user-as-reader who does not watch
-  the implementation. Entries are appended at done-state
-  notifications and mirror the Notify text verbatim. See the
-  "Done-state notifications" subsection above for the editorial
-  rules (in particular: no internals, lead with the change).
-
 Together these answer three questions: "what is the language right
 now?" (the `design/` ledger), "how did we get here?" (per-iter
 journals, specs, plans), and "what's next?" (roadmap).
-`WhatsNew.md` is the user-facing mirror of the journals — the same
-history, told without internals.