fix(core): restore drawing buffer sync for attached GL contexts on resize

[chrisgervang]

Summary

Fixes a resize regression in interleaved mode (MapboxOverlay / MapLibre) introduced by the CanvasContext adoption PR.

• Restores the setDrawingBufferSize call in the attached-GL onResize callback

Root cause

webgl2Adapter.attach() sets autoResize: false on the canvas context (luma webgl-adapter.ts:73). This means luma's _updateDrawingBufferSize() skips updating the drawing buffer when the ResizeObserver fires — it only updates cssWidth/cssHeight.

The parent PR removed the manual setDrawingBufferSize call assuming luma would handle it, but luma explicitly does not for autoResize: false contexts. The result: viewport dimensions updated correctly on resize, but rendering continued into the old-sized framebuffer.

Test plan

• yarn vitest run test/modules/core/lib/deck.spec.ts — 20/20 pass
• Manual: basemap-browser example, MapLibre interleaved mode, resize window — deck overlay stays aligned with basemap

🤖 Generated with Claude Code

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Note

Medium Risk
Touches core resize handling for attached WebGL contexts; small change but it affects rendering correctness in interleaved/overlay integrations and could have platform-specific side effects.

Overview
Restores manual drawing-buffer resizing for attached WebGL contexts by calling canvasContext.setDrawingBufferSize() inside the webgl2Adapter.attach() onResize handler before Deck updates viewport state and forwards to any user onResize callback.

This prevents resize events from updating only CSS/viewport dimensions while continuing to render into an old-sized framebuffer when autoResize is disabled for attached contexts (e.g., Mapbox/MapLibre interleaved overlays).

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