feat: add dockerized 3proxy control plane backend

server/lib/store.ts

@@ -0,0 +1,30 @@
+import fs from 'node:fs/promises';
+import path from 'node:path';
+import type { ControlPlaneState } from '../../src/shared/contracts';
+import { createDefaultState } from './config';
+
+export class StateStore {
+  constructor(private readonly statePath: string) {}
+
+  async read(): Promise<ControlPlaneState> {
+    await fs.mkdir(path.dirname(this.statePath), { recursive: true });
+
+    try {
+      const raw = await fs.readFile(this.statePath, 'utf8');
+      return JSON.parse(raw) as ControlPlaneState;
+    } catch (error) {
+      if ((error as NodeJS.ErrnoException).code !== 'ENOENT') {
+        throw error;
+      }
+
+      const fallback = createDefaultState();
+      await this.write(fallback);
+      return fallback;
+    }
+  }
+
+  async write(state: ControlPlaneState): Promise<void> {
+    await fs.mkdir(path.dirname(this.statePath), { recursive: true });
+    await fs.writeFile(this.statePath, `${JSON.stringify(state, null, 2)}\n`, 'utf8');
+  }
+}