<#
.SYNOPSIS
Creates a SHA-256 file inventory without changing the source directory.
.EXAMPLE
./Get-FileManifest.ps1 -Path ./deployment | ConvertTo-Json | Set-Content ./manifest.json
#>
[CmdletBinding()]
param(
    [Parameter(Mandatory)][ValidateNotNullOrEmpty()][string]$Path
)
$ErrorActionPreference = 'Stop'
$manifestRoot = (Resolve-Path -LiteralPath $Path).ProviderPath
if (-not (Test-Path -LiteralPath $manifestRoot -PathType Container)) {
    throw 'Path must point to a directory.'
}
Get-ChildItem -LiteralPath $manifestRoot -File -Recurse |
    Where-Object { -not ($_.Attributes -band [IO.FileAttributes]::ReparsePoint) } |
    Sort-Object FullName |
    ForEach-Object {
        [pscustomobject]@{
            Path = [IO.Path]::GetRelativePath($manifestRoot, $_.FullName).Replace('\', '/')
            Bytes = $_.Length
            SHA256 = (Get-FileHash -LiteralPath $_.FullName -Algorithm SHA256).Hash.ToLowerInvariant()
        }
    }