feat: integrate Spatie Media Library (#4)

- Added Spatie Media Library
- Added media library configuration file
- Updated Entry model to support media handling
- Added featured image upload with gallery selection and preview
- Added login tests with Dusk for user authentication
- Added Dusk test for featured image selection

Co-authored-by: jon brookes <marshyon@gmail.com>
Reviewed-on: https://codeberg.org/headshed/share-lt/pulls/4

database/migrations/2026_01_02_160151_create_media_table.php

@@ -0,0 +1,30 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('media', function (Blueprint $table) {
+            $table->id();
+            $table->morphs('model');
+            $table->uuid()->nullable()->unique();
+            $table->string('collection_name');
+            $table->string('name');
+            $table->string('file_name');
+            $table->string('mime_type')->nullable();
+            $table->string('disk');
+            $table->string('conversions_disk')->nullable();
+            $table->unsignedBigInteger('size');
+            $table->json('manipulations');
+            $table->json('custom_properties');
+            $table->json('generated_conversions');
+            $table->json('responsive_images');
+            $table->unsignedInteger('order_column')->nullable()->index();
+            $table->nullableTimestamps();
+        });
+    }
+};