[raffaelemancuso]

Clicking a task that is already open in the details view currently does nothing, and the open task always shows its subtasks, so it cannot be folded from the list (see #2028).

With this change, clicking the title area of the open task hides or shows its subtasks, like "Hide subtasks" / "Show subtasks" in the actions menu (same X-OC-HIDESUBTASKS property). The details view stays open, and opening the task again later shows its subtasks as before.

Unchanged: clicks on tasks that are not open (they still open them), tasks without subtasks, the checkbox, tags and actions menu, and double click to edit the summary (the second click of a double click is ignored; a double click on a task that is already open still toggles once before editing).

Tests: new tests/javascript/unit/components/TaskBody.spec.js (5 tests, 4 of them fail without the change); the full suite and eslint pass.

AI disclosure: the code, the tests and this description were drafted with Claude Code (claude-opus-5-5), as recorded in the Assisted-by trailer.

🤖 Generated with Claude Code

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