feat: add placements

[fiji-flo]

No description provided.

[caugner]

First round of review (until client/src/setupProxy.js)

[caugner]

This sign secret not specific to Kevel?

[caugner]

Feel like these should be objects 🤔

[caugner]

Second round or review (A-Z)

[caugner]

We wanted to pull the check inside here:

Suggested change

	navigator?.sendBeacon?.(
	navigator && navigator.sendBeacon?.(

[LeoMcA]

Does this make a difference?

[caugner]

We only use these in one branch.

[caugner]

I'd almost extract these into const HTTP_405_METHOD_NOT_ALLOWED for reuse.

[LeoMcA]

Perhaps just make this optional in the type in placement.tsx, and deal with a null value there?

[LeoMcA]

This whole section of code is a bit weird, how about:

Suggested change

	function getIsDocumentHidden() {
	if (typeof document !== "undefined") {
	return !document.hidden;
	}
	return false;
	}
	export function usePageVisibility() {
	const [isVisible, setIsVisible] = React.useState(getIsDocumentHidden());
	const onVisibilityChange = () => setIsVisible(getIsDocumentHidden());
	useEffect(() => {
	if (typeof document !== "undefined") {
	const visibilityChange = "visibilitychange";
	document.addEventListener(visibilityChange, onVisibilityChange, false);
	return () => {
	document.removeEventListener(visibilityChange, onVisibilityChange);
	};
	}
	});
	return isVisible;
	}
	export function usePageVisibility() {
	const [isVisible, setIsVisible] = React.useState(
	typeof document === "undefined"
	? false
	: document.visibilityState === "visible"
	);
	useEffect(() => {
	const onVisibilityChange = () =>
	setIsVisible(document.visibilityState === "visible");
	document.addEventListener("visibilitychange", onVisibilityChange);
	return () => {
	document.removeEventListener("visibilitychange", onVisibilityChange);
	};
	}, []);
	return isVisible;
	}
	}