feat: add trust_proxy config option for reverse proxy deployments

[ppastur]

Resolves #413

When deployed behind a reverse proxy, express-rate-limit warns that trust proxy is not set. Add a trust_proxy config option that calls app.set('trust proxy', value) when present.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[codecov-commenter]

⚠️ Please install the to ensure uploads and comments are reliably processed by Codecov.

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.18%. Comparing base (a42f280) to head (53e4fa2).
❗ Your organization needs to install the Codecov GitHub app to enable full functionality.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #414      +/-   ##
==========================================
+ Coverage   62.58%   72.18%   +9.59%     
==========================================
  Files          33       33              
  Lines         850      852       +2     
  Branches      236      237       +1     
==========================================
+ Hits          532      615      +83     
+ Misses        269      207      -62     
+ Partials       49       30      -19     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[ppastur]

Hi @ryanlelek ,
Just following up on this PR — I noticed the CI build is showing a failure, but from what I can tell, it looks like it may be related to the FOSSA step not having access to the API key from a fork PR, rather than the code changes themselves. The test suite job passed cleanly.

That said, if there's anything you'd like me to change or fix on my end, happy to do so — just let me know!