Add NPC database table with server-side DataTable and per-NPC game notes

- Npc entity (village spreadsheet columns) + game_notes text field for
  the DM's live play notes, plus updated_at touched on every change
- Race / VillageStatus / BloodCartInvolvement / MysteryImportance as
  string-backed PHP enums, rendered as dropdowns on the edit form
- /npcs: server-side DataTables (paging, global search and column sort
  all run in the backend via NpcRepository::findForDataTable); name cell
  links to the edit page, game notes shown truncated
- /npcs/{id}: Bootstrap-themed edit form (all fields + a large game
  notes textarea); Symfony forms now use the bootstrap_5 theme
- app.js: generic server-side DataTable wiring driven by data-* on the
  <table>/<th> (data-datatable-src, data-row-url, data-format)
- app:npc:import console command - upserts from data/npcs.csv by
  (family, name), never overwrites game_notes; --purge / --dry-run
- data/npcs.csv: 180 villagers exported from the working spreadsheet

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

migrations/Version20260906125931.php

@@ -0,0 +1,30 @@
+<?php
+
+declare(strict_types=1);
+
+namespace DoctrineMigrations;
+
+use Doctrine\DBAL\Schema\Schema;
+use Doctrine\Migrations\AbstractMigration;
+
+/**
+ * Auto-generated Migration: Please modify to your needs!
+ */
+final class Version20260906125931 extends AbstractMigration
+{
+    public function getDescription(): string
+    {
+        return 'Create npc table (village population + per-NPC game notes)';
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->addSql('CREATE TABLE npc (id INT AUTO_INCREMENT NOT NULL, family VARCHAR(120) NOT NULL, name VARCHAR(160) NOT NULL, age SMALLINT DEFAULT NULL, race VARCHAR(255) NOT NULL, occupation VARCHAR(160) DEFAULT NULL, relationships LONGTEXT DEFAULT NULL, village_status VARCHAR(255) NOT NULL, blood_cart_involvement VARCHAR(255) NOT NULL, mystery_importance VARCHAR(255) NOT NULL, game_notes LONGTEXT DEFAULT NULL, updated_at DATETIME DEFAULT NULL, UNIQUE INDEX uniq_npc_family_name (family, name), PRIMARY KEY (id)) DEFAULT CHARACTER SET utf8mb4');
+    }
+
+    public function down(Schema $schema): void
+    {
+        // this down() migration is auto-generated, please modify it to your needs
+        $this->addSql('DROP TABLE npc');
+    }
+}