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diff --git a/client/node_modules/type-fest/source/require-exactly-one.d.ts b/client/node_modules/type-fest/source/require-exactly-one.d.ts
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+++ b/client/node_modules/type-fest/source/require-exactly-one.d.ts
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+// TODO: Remove this when we target TypeScript >=3.5.
+type _Omit<T, K extends keyof any> = Pick<T, Exclude<keyof T, K>>;
+
+/**
+Create a type that requires exactly one of the given keys and disallows more. The remaining keys are kept as is.
+
+Use-cases:
+- Creating interfaces for components that only need one of the keys to display properly.
+- Declaring generic keys in a single place for a single use-case that gets narrowed down via `RequireExactlyOne`.
+
+The caveat with `RequireExactlyOne` is that TypeScript doesn't always know at compile time every key that will exist at runtime. Therefore `RequireExactlyOne` can't do anything to prevent extra keys it doesn't know about.
+
+@example
+```
+import {RequireExactlyOne} from 'type-fest';
+
+type Responder = {
+	text: () => string;
+	json: () => string;
+	secure: boolean;
+};
+
+const responder: RequireExactlyOne<Responder, 'text' | 'json'> = {
+	// Adding a `text` key here would cause a compile error.
+
+	json: () => '{"message": "ok"}',
+	secure: true
+};
+```
+*/
+export type RequireExactlyOne<ObjectType, KeysType extends keyof ObjectType = keyof ObjectType> =
+	{[Key in KeysType]: (
+		Required<Pick<ObjectType, Key>> &
+		Partial<Record<Exclude<KeysType, Key>, never>>
+	)}[KeysType] & _Omit<ObjectType, KeysType>;