feat: agent token, auth.agent middleware, /mcp route with HadoServer skeleton

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

core/app/Models/AgentToken.php

@@ -0,0 +1,30 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+
+class AgentToken extends Model
+{
+    protected $guarded = [];
+
+    public function user(): BelongsTo
+    {
+        return $this->belongsTo(User::class);
+    }
+
+    /** Выпускает (или перевыпускает) токен пользователя; возвращает открытый токен — показать один раз. */
+    public static function issue(User $user): string
+    {
+        $token = 'hado_agent_'.bin2hex(random_bytes(32));
+        static::updateOrCreate(['user_id' => $user->id], ['token_hash' => hash('sha256', $token)]);
+
+        return $token;
+    }
+
+    public static function findByToken(string $token): ?self
+    {
+        return static::where('token_hash', hash('sha256', $token))->first();
+    }
+}