getProjection() in @deck.gl/mapbox can throw instead of returning undefined when called before the map's style is assigned #10549

Description

getProjection() in @deck.gl/mapbox's deck-utils.ts can throw when called
before the underlying map's style is assigned, instead of returning
undefined the way its callers (e.g. MapboxOverlay#_onAddInterleaved /
getDefaultView) expect for "not ready yet, default to mercator".

export function getProjection(map: Map): 'mercator' | 'globe' {
  const projection = map.getProjection?.();
  // ...

This guards against the method being absent (?.), but not against the
call itself throwing.

Repro

• @deck.gl/mapbox@9.3.9, maplibre-gl@5.24, react-map-gl (maplibre entry
  point), React 19, MapboxOverlay in interleaved mode via useControl.
• Under React 19 StrictMode, the dev-only double-invoke of mount effects
  adds, removes, and re-adds the same overlay instance within a single mount.
  On the third addControl call, map.getProjection() is invoked before the
  map's style has been attached.
• maplibre-gl@5.24's own Map.prototype.getProjection() is
  return this.style.getProjection(); with no guard on this.style — so
  calling it before the style exists throws
  (Cannot read properties of undefined (reading 'getProjection')) rather
  than returning undefined.
• Since @deck.gl/mapbox's getProjection() only guards the method being
  absent, the throw propagates out of _onAddInterleaved, surfacing as an
  uncaught error in the host application.

Reproduced live with Playwright (response-body interception instrumenting
getProjection): with StrictMode active, exactly 3 getProjection calls
fire on mount, and the 3rd hits a still-styleless map.

Related

PR #9794 fixed a similar timing/undefined issue in the later
_handleStyleChange callback path ("getDefaultView is called too early,
and getProjection returns undefined... the bug only happens with React,
in interleaved mode"), but the fix doesn't cover this earlier onAdd-time
call site, which can throw rather than return undefined.

Suggested fix

Wrap the map.getProjection?.() call in a try/catch inside getProjection(),
treating a throw the same as the already-handled undefined case:

export function getProjection(map: Map): 'mercator' | 'globe' {
  let projection;
  try {
    projection = map.getProjection?.();
  } catch {
    projection = undefined;
  }
  const type =
    // maplibre projection spec
    projection?.type ||
    // ...

We've worked around this locally with a pnpm patch applying exactly this
change to @deck.gl/mapbox@9.3.9 and would be happy to open a PR with it if
that's useful.