fix(core): do not draw before the canvas is sized

[xecanto]

Closes #10599

Background

A Deck that creates its own canvas draws its first frames into the default 300x150 drawing buffer, stretched over the real canvas size, until luma reports the size. The issue describes this for MapboxOverlay, but a standalone Deck with a parent does the same. Deck now sizes the canvas when it creates it and skips frames until luma has measured it.

Change List

• Deck: apply the CSS size when the canvas is created
• Deck: skip frames until the owned canvas is measured
  • Not applied when width and height are numbers
  • A canvas with no layout size is not drawn until it has one
• Unit tests
• Ran vitest --project headless, --project render and yarn lint

---

Note

Medium Risk
Touches core redraw() and canvas lifecycle in deck.ts, but behavior is gated to auto-created canvases without explicit numeric dimensions; mis-detection could delay or skip an initial draw.

Overview
Fixes first-frame rendering when Deck auto-creates its own canvas (e.g. MapboxOverlay): layers were briefly drawn into the default 300×150 drawing buffer and stretched until luma measured the real size.

Deck now applies CSS width/height as soon as the owned canvas is created, tracks _ownedCanvasNeedsSize when numeric width/height props are not set, and skips redraw() until the canvas has non-zero layout and luma reports a resize (or the context was already initialized on device setup). Redraw flags are preserved so the next resize still paints.

Mapbox overlay tests assert the first completed frame uses the map’s 400×300 drawing buffer, including when the overlay DOM is inserted late.

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[greptile-apps]

Confidence Score: 5/5

[Medium impact] The PR appears safe to merge; no actionable issue remains.

Summary

Deck applies CSS sizing when it creates a canvas and holds redraws until that canvas has a measured layout size.

• Deck waits for an owned canvas to have a real size before drawing.

Diagram

%%{init: {'theme': 'neutral'}}%%
flowchart TD
  A[Deck creates canvas] --> B[Apply CSS size]
  B --> C{Both size props are numbers?}
  C -->|Yes| F[Allow redraw]
  C -->|No| D[Hold redraws]
  D --> E[Luma initialization or resize]
  E --> G{Canvas has layout size?}
  G -->|No| D
  G -->|Yes| F

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