perf(proxy): parallelize provider proxy overlay lookups

[terence71-glitch]

Summary

Follow-up to #2963, which was merged before this optimization commit landed.

This keeps the existing provider registry overlay behavior unchanged, but avoids resolving provider assignment proxy details sequentially. Provider assignment proxy lookups now run in parallel with Promise.all, then successful results are applied to config.providers.

Validation

• npx eslint src/app/api/settings/proxy/route.ts
• npx cross-env DISABLE_SQLITE_AUTO_BACKUP=true node --import tsx --test --test-force-exit tests/unit/route-edge-coverage.test.ts

Result: 15 pass, 0 fail.

[gemini-code-assist]

Code Review

This pull request refactors the proxy retrieval logic in src/app/api/settings/proxy/route.ts to fetch proxy configurations in parallel using Promise.all instead of sequentially. The reviewer suggested a further optimization to deduplicate proxy lookups by extracting unique proxyIds before querying, which would prevent redundant database queries when multiple assignments share the same proxy.

[gemini-code-assist]

Optimization: Deduplicate Proxy Lookups

If multiple provider assignments share the same proxy (which is a very common configuration), the current implementation will perform redundant database queries for the same proxyId.

We can optimize this by:

1. Filtering the assignments to find valid ones.
2. Extracting the unique proxyIds.
3. Fetching only the unique proxies in parallel.
4. Mapping them back to the providers.

This reduces the number of database queries and event loop microtasks.

      const validAssignments = providerAssignments.filter(
        (assignment) => assignment.scopeId && assignment.proxyId
      );

      const uniqueProxyIds = Array.from(
        new Set(validAssignments.map((assignment) => assignment.proxyId as string))
      );

      const proxyDataResults = await Promise.all(
        uniqueProxyIds.map(async (proxyId) => {
          const proxyData = await getProxyById(proxyId, { includeSecrets: true });
          return { proxyId, proxyData };
        })
      );

      const proxyMap = new Map<string, NonNullable<typeof proxyDataResults[number]["proxyData"]>>();
      for (const { proxyId, proxyData } of proxyDataResults) {
        if (proxyData) {
          proxyMap.set(proxyId, proxyData);
        }
      }

      for (const assignment of validAssignments) {
        const proxyData = proxyMap.get(assignment.proxyId!);
        if (!proxyData) continue;
        config.providers[assignment.scopeId!] = {
          type: proxyData.type,
          host: proxyData.host,
          port: proxyData.port,
          username: proxyData.username,
          password: proxyData.password,
        };
      }