task: preset list is a hardcoded 46-entry Dart literal with no update path -- and zero 500 kHz options #648

Parent: #647 (feature: MESH 500). Cross-ref firmware #1064.

Finding [verified: lib/models/radio_settings.dart @ 2026-09-09]

The regional preset list is a static Dart literal compiled into the app -- 46 entries, no fetch, no update mechanism. A user only ever sees the presets that shipped with their build.

Consequences:

• Zero of the 46 entries use 500 kHz bandwidth, so the client cannot offer a US FCC-compliant preset at all.
• New community presets can never appear without an app release. The stock MeshCore client, by contrast, pulls from a live server-side registry and gains new regions without shipping a build.
• Our list has diverged from upstream's rather than lagging it: 26 Russia city-level presets and USA Arizona are ours alone (inherited from the zjs81/meshcore-open ancestry); Philly, SoCal, Brazil, Costa Rica, Hungary, Netherlands x2 and Slovakia exist upstream and not here.

Not a bug report, and not a fix proposal

Recording the current state so the design decision on #647 rests on fact. Whether the answer is a live registry, our own published list, or a curated static list is explicitly the owner's open question -- see the architecture note on the parent. Do not implement a fetch on the strength of this issue.

Acceptance

The parent's design decision can cite a verified description of what we ship today. If a fix follows, it is filed separately once the owner has framed the direction.

Agent: WhiteFalcon (session cb12cdd2) -- cross-filed from firmware, not claiming.