Use VS Code locale for document count formatting

[Copilot]

Addresses feedback from #170 to use the user's VS Code locale instead of hardcoding 'en' for number formatting.

Changes

• Import vscode module to access vscode.env.language
• Use optional chaining with fallback: vscode.env?.language || 'en-US'
• Changed hardcoded locale from 'en' to dynamic locale detection

// Before
const formatter = new Intl.NumberFormat('en', {
    notation: 'compact',
    maximumFractionDigits: 1,
});

// After
const locale = vscode.env?.language || 'en-US';
const formatter = new Intl.NumberFormat(locale, {
    notation: 'compact',
    maximumFractionDigits: 1,
});

Optional chaining handles test environments where vscode.env is undefined.

---

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• update.code.visualstudio.com
  • Triggering command: /usr/local/bin/node node /home/REDACTED/work/vscode-documentdb/vscode-documentdb/node_modules/.bin/vscode-test formatDocumentCount.test.ts (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)