[Bug] List field "Expand All / Collapse All" buttons not rendered in "top" position when using controls: both

[olygoelements]

In forms/fields/list/list.html.twig, the collapsible variable is computed inside the {% for key, val in value %} loop (line ~90), which means it is undefined at the time the top block of collection-actions is rendered.

Result : When using controls: both in a blueprint list field, the "Expand All" and "Collapse All" buttons appear correctly at the bottom of the list, but are missing at the top.

To reproduce :

yaml
  type: list
  style: vertical
  controls: both
  collapsed: true
  btnLabel: 'Add item'
  fields:
    .field_a:
      type: text
      label: 'Field A'
    .field_b:
      type: text
      label: 'Field B'

Expected : "Expand All", "Collapse All" and "+ Add item" buttons visible both at top and bottom.
Actual : Only "+ Add item" appears at top. "Expand All" / "Collapse All" are missing at top.

Root cause :

twig
{# In list.html.twig — collapsible is set here, INSIDE the for loop #}
{% for key, val in value %}
    {% set collapsible = field.fields|length > 1 and ... %}  {# ← too late #}
But the top block is rendered before this loop :
twig{% if fieldControls in ['top', 'both'] %}
    <div class="collection-actions">
        {% if collapsible %}   {# ← undefined here, evaluates to false #}

Fix :
Move the collapsible declaration before {% block contents %} :

twig
{% set fieldControls = field.controls|default('bottom') %}

{# FIX: compute collapsible before block contents so it's available in both top AND bottom collection-actions #}
{% set collapsible = field.fields is defined and field.fields|length > 1 and (field.collapsible is not defined or field.collapsible) %}

{% block contents %}

This one-line move makes collapsible available to both the top and bottom collection-actions blocks without changing any other behavior.

Affected file :
user/plugins/form/templates/forms/fields/list/list.html.twig
(also reproduced in user/plugins/admin/themes/grav/templates/forms/fields/list/list.html.twig)
Grav version : tested on 1.7.x
Plugin form version : tested on current

[sridharkalaibala]

Opened #2520 with the field-level collapsible calculation moved before the contents block. On current develop it is inside the field.fields condition immediately before the item loop, which is still too late for the top action group.

I rendered the actual Admin template across 54 control-placement/field-count/collapse-setting/value combinations. The original template had 16 missing-button assertions across 8 configurations; the change passes all cases and preserves Add Item counts. The PR describes the standalone Twig harness and its limits. The Form plugin's current develop tree does not contain the list-template path mentioned in the report, so this fixes the existing Admin template.