Advanced field round-trip

[jonocodes]

Part of #82

Question

How should the editor handle Widget/Layout fields it does not touch? The Pydantic models have fields the v1 editor will not expose in its UI (macros, media_http, previous_action, art_source, empty_state, sensor configuration for meters/stats). Options: silently round-trip these fields (include them in the model dump on save, never show them), or warn before saving that unrecognized fields will be preserved untouched, or require an explicit "advanced fields" toggle. Decide the behavior.

[jonocodes]

Resolution

Grounded in daemon/deckd/layouts.py: Widget, Action, Layout all use ConfigDict(extra="forbid") — so there are no unknown fields. Every field the editor won't expose (macro, media_http, art_source, controls, previous_action/next_action/volume_up_action/volume_down_action, empty_state, meter/stats sensor config source/min/max/metrics) is a declared, daemon-known field the v1 UI simply doesn't render. The ticket reframes to: how does the editor avoid destroying known fields it doesn't show.

Preservation mechanism — client opaque pass-through. The daemon serializes the full validated model to the client, so the client receives every field even when it renders no UI for it. The client's edit model retains all fields verbatim (unrendered ones as opaque blobs) and echoes them untouched in the full-snapshot PUT. Keeps #84's contract intact (PUT stays an idempotent full-snapshot replace — no daemon-side merge semantics) and makes field deletion unambiguous: clearing a field = omitting it from the snapshot. Requires the TS edit model to carry unrendered keys rather than parsing widgets into a narrow shape that drops them.

UX policy — pure silent round-trip. No warning, no toggle, no badge. A save-time warning would fire on every media/meter save and train dismissal; a full advanced editor is out-of-scope (it edits the very fields — macros, media config — the map defers). The data rides along invisibly; the editor shows only the fields it supports.

Unsupported-kind widgets — opaque placeholder, structurally editable. A widget whose kind the editor can't field-edit renders as a labeled placeholder tile in the reflow canvas, reorderable and deletable (list-position ops that don't touch internals), with no editable property fields. Rationale: ADR-0010 reflow is ordered-list positioning, so a media widget's place matters and must be movable; hiding it (would desync the canvas from the live deck — a slot consumed invisibly) and locking it (can't rearrange) are both worse.

• Opaque-placeholder bucket = media family only: media, mediabrowser. Not insertable from the palette.

blank is editor-supported, not opaque. blank takes only size (ADR-0010's deliberate-gap primitive; the model validator forbids every other field), and size is exactly what the reflow editor manages. A reflow editor must be able to insert gaps, so blank is insertable from the palette, size-editable, reorderable, deletable — alongside button/meter/stats.

Summary — editor-supported kinds: button, meter, stats, blank (native, field-editable within v1's surface, insertable). Opaque placeholders: media, mediabrowser (reorder/delete only, data preserved, not insertable).