feat: enums, schema and models for hado core

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BCrwHHnGCB5XH968Nxokqw

core/app/Models/Source.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+
+class Source extends Model
+{
+    protected $guarded = [];
+
+    public function events(): HasMany
+    {
+        return $this->hasMany(Event::class);
+    }
+}