{#- The `→ 22:30` next-update suffix (ADR-0044 decision 5, as amended): the check
    time's companion wherever that time shows, for the nodes that carry run facts —
    the sole-check mount and the ancestors that inherit its stamp. **Absolute, at
    minute precision like the check time itself** (seconds earn their room nowhere
    on the grid), and **suppressed when it would render identical to the shown
    check time** — an arrow to the very value beside it says nothing, so a
    sub-minute schedule shows a bare time and the arrow appears exactly when it
    adds information. Absolute is freeze-safety: when polling fails, the
    client-side staleness dims the page and leaves it on screen, and a frozen
    relative "in 4m" is a lie that still looks live, while a frozen `→ 22:30`
    stays true and recedes into the past. A stalled check shows a next update
    already gone by — honest, and the staleness WARN beside it carries the alarm.

    ``moment_hm`` is the ``%H:%M`` form of the check time actually shown beside
    this suffix, so the suppression compares at display precision, in display
    timezone. Kept in its own side-effect-free partial: importing a macro executes
    the source template's body, so shared macros must not live in a page partial
    (the `_status_cue.html` lesson). -#}
{% macro next_update(next_iso, moment_hm) -%}
{%- if next_iso -%}
{%- set next_hm = next_iso | localtime("%H:%M") -%}
{%- if next_hm != moment_hm %} → {{ next_hm }}{% endif -%}
{%- endif -%}
{%- endmacro %}