Add condition_aggregator_met_norway (and sibling condition_aggregator_digitraffic) Dart adapters to ClientLibraries.md

[aki1770-del]

Summary

Just letting the team know two Dart adapters exist that consume api.met.no/weatherapi/locationforecast/2.0/compact, in case they fit the third-party client listing maintained at doc/ClientLibraries.md. Not asking for any code change here yet — would like an acknowledgment first.

The packages

Both adapters live in a small Dart interface for driver-facing weather and traffic advisories on navigation HMIs:

• condition_aggregator_met_norway — consumes locationforecast/2.0/compact, maps the next-hour forecast slice to a typed advisory event (severity / certainty / urgency). Pure Dart, public-API only, no scraping.
• condition_aggregator_digitraffic — sibling adapter for Finland's Fintraffic Digitraffic open feed; mentioned for context since the two ship together as the start of a Nordic-region adapter family.

Source on GitHub: https://github.com/aki1770-del/SNGNav (BSD-3-Clause for the adapter code).

Terms-of-service compliance

For the MET Norway adapter:

• Mandatory User-Agent header is set; the package README points downstream integrators at overriding it under their own application identity per the published terms.
• Coordinates are truncated to 4 decimals before request, per the terms documented at https://api.met.no/doc/TermsOfService.
• The CC-BY-4.0 attribution string is surfaced verbatim in every emitted advisory's description field: "Source: Norwegian Meteorological Institute (Meteorologisk institutt / MET Norway). CC BY 4.0 — api.met.no." — and the README binds integrators to surfacing that line at the HMI layer.

What this issue is asking

Would the team be open to adding these two adapters to doc/ClientLibraries.md (a Dart section, or a new one if there isn't one yet)?

For shape, PR #3 from @timharek (adding a Go package and CLI link to the same file) is the closest existing example. If yes, we will open a PR with one-line listing entries against the responsive branch and quote your reply in the PR body. If the Dart-client listing has a different canonical home, please point us at it. If silence or "not now" — that is also a valid answer and we will not push.

What this issue is not asking

• Not a code change to weatherapi-docs beyond a listing entry.
• Not a feature request against api.met.no (we noticed roadforecast/2.0 returns HTTP 404 publicly at our check on 2026-05-24; we read that as intentional access scope and are not raising it here).
• Not asking for maintainer time on review or merge — only an acknowledgment that the third-party listing path is open to a Dart entry.

Closing

Thank you for the public, well-documented CC-BY-4.0 forecast feed. Nordic-region drivers rely on it daily, and the adapter exists so that downstream navigation products can surface MET Norway's forecast with the attribution credit honored at the driver-facing surface.

Filing as aki1770-del (Akihiko Komada).