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>

config/packages/twig.yaml

@@ -1,5 +1,6 @@
 twig:
     file_name_pattern: '*.twig'
+    form_themes: ['bootstrap_5_layout.html.twig']
 
 when@test:
     twig: