feat: add server and frontend initial - wood chopping

packages/server/src/persist/db.ts

@@ -0,0 +1,56 @@
+import { mkdirSync } from 'node:fs';
+import path from 'node:path';
+import { DatabaseSync } from 'node:sqlite';
+import type { ViewerRecord } from '../sim/world';
+
+/**
+ * Тонкий слой persist на встроенном node:sqlite — без нативных сборок и
+ * install-скриптов. При необходимости заменяется (better-sqlite3/postgres)
+ * без изменений в остальном коде.
+ */
+export class Db {
+  private readonly db: DatabaseSync;
+
+  constructor(dbPath: string) {
+    if (dbPath !== ':memory:') {
+      mkdirSync(path.dirname(dbPath), { recursive: true });
+    }
+    this.db = new DatabaseSync(dbPath);
+    this.db.exec('PRAGMA journal_mode = WAL');
+    this.db.exec(`
+      CREATE TABLE IF NOT EXISTS viewers (
+        channel_id TEXT NOT NULL,
+        user_id    TEXT NOT NULL,
+        name       TEXT NOT NULL,
+        color      TEXT NOT NULL,
+        xp         INTEGER NOT NULL DEFAULT 0,
+        logs       INTEGER NOT NULL DEFAULT 0,
+        updated_at INTEGER NOT NULL,
+        PRIMARY KEY (channel_id, user_id)
+      )
+    `);
+  }
+
+  loadViewers(channelId: string): ViewerRecord[] {
+    const rows = this.db
+      .prepare('SELECT user_id, name, color, xp, logs FROM viewers WHERE channel_id = ?')
+      .all(channelId) as Array<{ user_id: string; name: string; color: string; xp: number; logs: number }>;
+    return rows.map((r) => ({ userId: r.user_id, name: r.name, color: r.color, xp: r.xp, logs: r.logs }));
+  }
+
+  saveViewer(channelId: string, v: ViewerRecord): void {
+    this.db
+      .prepare(
+        `INSERT INTO viewers (channel_id, user_id, name, color, xp, logs, updated_at)
+         VALUES (?, ?, ?, ?, ?, ?, ?)
+         ON CONFLICT(channel_id, user_id) DO UPDATE SET
+           name = excluded.name, color = excluded.color, xp = excluded.xp,
+           logs = excluded.logs, updated_at = excluded.updated_at`,
+      )
+      .run(channelId, v.userId, v.name, v.color, v.xp, v.logs, Date.now());
+  }
+
+  close(): void {
+    this.db.close();
+  }
+}