History: AI-driven alternate-history simulator

Pax Historia-style sim where the LLM is the world engine.

- React 19 + Vite 6 + Tailwind v4 + shadcn/ui frontend
- Express single-port backend (/api + /sse + built client + SPA fallback)
- SQLite (better-sqlite3) persistence, one row per game
- MapLibre choropleth map (OpenFreeMap dark + ISO_A3 regions)
- Defensive turn loop: strip fences, balanced-{} extract, parse, clamp 0-100,
  retry-once nudge, generic 'unclear' fallback; never crashes on bad output
- 5 seed presets (wwii-1939, coldwar-1955, modern-2025, no-wwii-1940, aegis-2400)
- LLM client over native fetch w/ injectable transport (mesh-bot pattern);
  LLM_STUB=1 deterministic transport for tests/e2e
- Unit (vitest, 19) + deterministic Playwright e2e
- Multi-stage node:22-slim Docker + Traefik (history.dev.kkhost.pl:4321)

Co-Authored-By: OpenCode <opencode@users.noreply.github.com>

server/presets.ts

@@ -0,0 +1,26 @@
+// Load presets from disk. Each preset is a JSON file; index.json is the manifest
+// used to render the picker cards. The store is created with the resolved presets
+// directory so it works from repo root (dev) and /app (Docker) alike.
+import { readFileSync } from 'node:fs';
+import type { Preset, PresetMeta } from '../shared/types';
+
+export interface PresetStore {
+  listMeta(): PresetMeta[];
+  get(id: string): Preset | null;
+}
+
+export function createPresetStore(dir: string): PresetStore {
+  const manifest = JSON.parse(readFileSync(`${dir}/index.json`, 'utf8')) as PresetMeta[];
+  return {
+    listMeta() {
+      return manifest;
+    },
+    get(id: string) {
+      try {
+        return JSON.parse(readFileSync(`${dir}/${id}.json`, 'utf8')) as Preset;
+      } catch {
+        return null;
+      }
+    },
+  };
+}