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/db.ts

@@ -0,0 +1,52 @@
+// SQLite persistence for games (one row per game id; the full GameState as JSON).
+import { mkdirSync } from 'node:fs';
+import path from 'node:path';
+import Database from 'better-sqlite3';
+import type { GameState } from '../shared/types';
+
+export interface Db {
+  save(state: GameState): void;
+  load(id: string): GameState | null;
+  listIds(): string[];
+  close(): void;
+}
+
+export function openDb(filePath: string): Db {
+  const dir = path.dirname(filePath);
+  if (dir) mkdirSync(dir, { recursive: true });
+  const db = new Database(filePath);
+  db.pragma('journal_mode = WAL');
+  db.exec(
+    `CREATE TABLE IF NOT EXISTS games (
+       id TEXT PRIMARY KEY,
+       data TEXT NOT NULL,
+       updated_at TEXT NOT NULL
+     )`,
+  );
+  const upsert = db.prepare(
+    `INSERT INTO games (id, data, updated_at) VALUES (?, ?, ?)
+     ON CONFLICT(id) DO UPDATE SET data = excluded.data, updated_at = excluded.updated_at`,
+  );
+  const byId = db.prepare('SELECT data FROM games WHERE id = ?');
+  const all = db.prepare('SELECT id FROM games ORDER BY updated_at DESC');
+  return {
+    save(state) {
+      upsert.run(state.id, JSON.stringify(state), new Date().toISOString());
+    },
+    load(id) {
+      const row = byId.get(id) as { data: string } | undefined;
+      if (!row) return null;
+      try {
+        return JSON.parse(row.data) as GameState;
+      } catch {
+        return null;
+      }
+    },
+    listIds() {
+      return (all.all() as { id: string }[]).map((r) => r.id);
+    },
+    close() {
+      db.close();
+    },
+  };
+}