fix: initialize proxy agent in sync-entry.ts to respect HTTP_PROXY (#347)

* Initial plan

* fix: initialize proxy agent in sync-entry.ts to respect HTTP_PROXY env var

Agent-Logs-Url: https://github.com/github-copilot-resources/copilot-metrics-viewer/sessions/2952bbf5-4bc5-44c2-9a5f-b1c7ae31aad1

Co-authored-by: karpikpl <3539908+karpikpl@users.noreply.github.com>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: karpikpl <3539908+karpikpl@users.noreply.github.com>
Co-authored-by: Piotr Karpala <karpik.pl@gmail.com>

Author: Copilot

server/sync-entry.ts

@@ -12,8 +12,36 @@
  *   - NUXT_GITHUB_TOKEN: GitHub personal access token
  *   - SYNC_DAYS_BACK: Number of days to sync (default: 28, uses bulk download)
  *   - DATABASE_URL: PostgreSQL connection string (or use PG* env vars)
+ *   - HTTP_PROXY: Optional HTTP/HTTPS proxy URL (e.g. http://proxy:8080)
+ *   - CUSTOM_CA_PATH: Optional path to a custom CA certificate file
  */
 
+// Initialize proxy agent before any fetch calls (mirrors server/plugins/http-agent.ts)
+import { ProxyAgent, setGlobalDispatcher } from 'undici';
+import { readFileSync, existsSync } from 'fs';
+
+if (process.env.HTTP_PROXY) {
+  try {
+    const tlsOptions = process.env.CUSTOM_CA_PATH ? (() => {
+      if (!existsSync(process.env.CUSTOM_CA_PATH!)) {
+        throw new Error(`CUSTOM_CA_PATH file not found: ${process.env.CUSTOM_CA_PATH}`);
+      }
+      return { tls: { ca: [readFileSync(process.env.CUSTOM_CA_PATH!)] } };
+    })() : {};
+
+    const proxyAgent = new ProxyAgent({
+      uri: process.env.HTTP_PROXY,
+      ...tlsOptions
+    });
+
+    setGlobalDispatcher(proxyAgent);
+    console.info(`Proxy agent initialized: ${process.env.HTTP_PROXY}`);
+  } catch (error) {
+    console.error('Failed to initialize proxy agent:', error);
+    process.exit(1);
+  }
+}
+
 import { syncBulk } from './services/sync-service';
 import { initSchema } from './storage/db';
 import { closePool } from './storage/db';