Add Open-Meteo adapter

[ankitranjan7]

Summary

• add Open-Meteo no-key public API adapter commands
• commands added:
  • webcmd open-meteo current <location>
  • webcmd open-meteo forecast <location>
  • webcmd open-meteo hourly <location>
  • webcmd open-meteo air-quality <location>
• support city names or lat,lon via Open-Meteo geocoding
• support --units metric|imperial for weather commands that expose weather units
• regenerate cli-manifest.json

Verification

• webcmd doctor
• direct endpoint probes returned HTTP 200 JSON for forecast hourly fields and air-quality hourly fields
• npm run build-manifest
• npm run typecheck
• npm run check:silent-column-drop
• npm run check:typed-error-lint
• npm test -- clis/open-meteo/open-meteo.test.js
• npm test
• live verified:
  • node dist/src/main.js open-meteo hourly Seattle --hours 2 --format json
  • node dist/src/main.js open-meteo air-quality Seattle --hours 2 --format json
• webcmd browser verify --strict-memory passed for open-meteo/hourly and open-meteo/air-quality with tightened local fixtures