chore: update document approval workflow and bug fixes

Modules/DocumentManagement/app/Models/DocumentVersion.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace Modules\DocumentManagement\Models;
+
+use App\Models\User;
+use App\Traits\HasPublicIdentifier;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class DocumentVersion extends Model
+{
+    use HasPublicIdentifier;
+
+    protected $fillable = [
+        'document_id', 'version_number', 'file_path', 'file_name',
+        'mime_type', 'file_size', 'uploaded_by', 'change_notes',
+    ];
+
+    public function document(): BelongsTo
+    {
+        return $this->belongsTo(Document::class);
+    }
+
+    public function uploader(): BelongsTo
+    {
+        return $this->belongsTo(User::class, 'uploaded_by');
+    }
+}