feat: complete person identity matching system with fuzzy detection, revert, and manual link

Implements the full identity matching engine: email matching (HIGH confidence),
fuzzy name matching with Levenshtein distance (MEDIUM confidence, upgradable to
HIGH with DOB tiebreaker), manual link/unlink, revert confirmed matches, and
automatic detection via PersonObserver. Includes 33 comprehensive tests, frontend
integration with confirm/dismiss/unlink UI, and match indicators in the persons list.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

api/app/Enums/IdentityMatchMethod.php

@@ -7,6 +7,15 @@ namespace App\Enums;
 enum IdentityMatchMethod: string
 {
     case EMAIL = 'email';
-    case PHONE = 'phone';
+    case NAME_FUZZY = 'name_fuzzy';
     case MANUAL = 'manual';
+
+    public function label(): string
+    {
+        return match ($this) {
+            self::EMAIL => 'E-mail match',
+            self::NAME_FUZZY => 'Naam match (vergelijkbaar)',
+            self::MANUAL => 'Handmatig gekoppeld',
+        };
+    }
 }