fix: await async VirtualDisplay.get() (fixes 'cannot open display: [object Promise]' on Docker/Linux)

[Kyzcreig]

Problem

camoufox-js's VirtualDisplay.get() is async (returns Promise<string> like ':0'), but launchBrowserInstance() in server.js calls it without await:

vdDisplay = localVirtualDisplay.get();

So vdDisplay is a Promise, which is then passed to launchOptions({ virtual_display: vdDisplay }) and stringified to "[object Promise]". Every Camoufox launch on Linux/Docker then fails with:

Error: cannot open display: [object Promise]

This breaks the Docker deployment entirely — /health shows browserRunning: false, browserConnected: false, the background pre-warm retries forever, and every POST /tabs returns 500 Internal server error. The log shows the tell: "xvfb virtual display started", "display": {} (an unresolved Promise rendered as {}) immediately followed by the launch failure.

Fix

Add the missing await:

vdDisplay = await localVirtualDisplay.get();

launchBrowserInstance() is already async and awaits launchOptions(...) a few lines below, so this is safe. After the fix the log correctly shows "display": ":0" and "camoufox launched".

Verification

Built the image (make build && make up) on an arm64 Mac (Docker), confirmed:

• GET /health → {"ok":true,"browserConnected":true,"browserRunning":true,...}
• POST /tabs for https://nowsecure.nl (a Cloudflare bot-detection test page) → tab created, GET /tabs/:id/snapshot returns the success content (NOWSECURE headings) with no Cloudflare interstitial.

One-line change; no behavior change beyond fixing the broken Linux/virtual-display launch path.