function Remove-PersonaConditionNode {
    <#
    .SYNOPSIS
        Removes a condition or nested group from a rule's condition tree (FR-028).

    .DESCRIPTION
        Two structural rules are enforced here rather than left to schema validation,
        because both would otherwise produce a document the schema calls invalid with
        no indication which editor action caused it:

          - The root group itself cannot be removed - a rule's `match` is required
            (RE-001). Delete the rule instead (Remove-PersonaConfigRule).
          - A group's last remaining condition cannot be removed - an empty
            `conditions` array violates the schema's `minItems: 1` on conditionGroup.
            Remove the parent group instead, or add a replacement first.

    .PARAMETER Group
        The rule's `match` condition group (the root).

    .PARAMETER Path
        Path (see Get-PersonaConditionNode) to the node to remove. Must not be empty.

    .OUTPUTS
        System.Object - the same Group, mutated in place, returned for convenience.
    #>
    [CmdletBinding()]
    [OutputType([object])]
    param(
        [Parameter(Mandatory)]
        [object] $Group,

        [Parameter(Mandatory)]
        [AllowEmptyCollection()]
        [int[]] $Path
    )

    if (@($Path).Count -eq 0) {
        throw "The root condition group cannot be removed this way - delete the rule instead."
    }

    # Special-cased at length 1 because PowerShell's range operator treats 0..-1 as
    # the two-element descending range (0, -1), not an empty range - the naive slice
    # would silently pick up the wrong parent for a top-level path.
    $parentPath = (@($Path).Count -eq 1) ? @() : @($Path)[0..($Path.Count - 2)]
    $index = @($Path)[-1]

    $parent = Get-PersonaConditionNode -Group $Group -Path $parentPath
    $children = @($parent.conditions)

    if ($index -lt 0 -or $index -ge $children.Count) {
        throw "Path segment $index is out of range - this group has $($children.Count) condition(s)."
    }

    if ($children.Count -eq 1) {
        throw 'This is the only condition in its group. A group requires at least one condition - remove the group itself instead, or add a replacement first.'
    }

    # Removed by position, not by value or reference - two structurally identical
    # sibling conditions are otherwise indistinguishable.
    $remaining = [System.Collections.Generic.List[object]]::new()
    for ($i = 0; $i -lt $children.Count; $i++) {
        if ($i -ne $index) { $remaining.Add($children[$i]) }
    }
    $parent.conditions = $remaining.ToArray()

    $Group
}