docs(todo): drop stale plan-strip format claims and fix the note's counts

The plan strip header has not emitted `<done>/<total> tasks · <n> in progress`
since #740 replaced it with `·`-joined per-status counts. Four sites still
quoted the old string: plan-summary.ts's module JSDoc, ui-conversation's
README pair, and the web-todo-display note pair.

The parallel-in-progress note's regression example mixed a four-item plan with
an eight-item row reading, and built-boot.snapshot.ts still called itself the
only test loading the built bundles.

packages/client/ui-conversation/src/client/toolviews/plan-summary.ts

@@ -2,9 +2,9 @@
  * Pure plan derivation for the todo_write row's one-line summary. Several items
  * may be `in_progress` at once — parallel work runs concurrent tasks, so a
  * summary built from one active item would silently drop the rest. The plan
- * strip header derives its own `<done>/<total> tasks · <n> in progress` counts
- * inline and shares nothing with this, so this stays inside the toolviews
- * domain rather than in `contract/` (the inter-domain face).
+ * strip header derives its own counts inline and shares nothing with this, so
+ * this stays inside the toolviews domain rather than in `contract/` (the
+ * inter-domain face).
  * @module
  */