Provide more documentation in JSDoc comments

[jcready]

Certainly there are already a lot of JSDoc comments in the code base providing helpful documentation especially handy inside IDEs that surface those. But there are also a lot of things that don't have JSDoc comments where they would definitely be useful.

For example, compare all the helpful information in the useQuery docs for all the query options to the JSDocs available for the query options:

query/packages/query-core/src/types.ts

Lines 70 to 80 in 3643b87

	retryDelay?: RetryDelayValue<TError>
	networkMode?: NetworkMode
	cacheTime?: number
	isDataEqual?: (oldData: TData | undefined, newData: TData) => boolean
	queryFn?: QueryFunction<TQueryFnData, TQueryKey>
	queryHash?: string
	queryKey?: TQueryKey
	queryKeyHashFn?: QueryKeyHashFunction<TQueryKey>
	initialData?: TData | InitialDataFunction<TData>
	initialDataUpdatedAt?: number | (() => number | undefined)
	behavior?: QueryBehavior<TQueryFnData, TError, TData>

Even less information is available when comparing the docs for the return type to what is available in the JSDoc comments:

query/packages/query-core/src/types.ts

Lines 374 to 402 in 3643b87

	export interface QueryObserverBaseResult<TData = unknown, TError = unknown> {
	data: TData | undefined
	dataUpdatedAt: number
	error: TError | null
	errorUpdatedAt: number
	failureCount: number
	failureReason: TError | null
	errorUpdateCount: number
	isError: boolean
	isFetched: boolean
	isFetchedAfterMount: boolean
	isFetching: boolean
	isLoading: boolean
	isLoadingError: boolean
	isInitialLoading: boolean
	isPaused: boolean
	isPlaceholderData: boolean
	isPreviousData: boolean
	isRefetchError: boolean
	isRefetching: boolean
	isStale: boolean
	isSuccess: boolean
	refetch: <TPageData>(
	options?: RefetchOptions & RefetchQueryFilters<TPageData>,
	) => Promise<QueryObserverResult<TData, TError>>
	remove: () => void
	status: QueryStatus
	fetchStatus: FetchStatus
	}

This means I often have to leave my IDE, open up the docs website, make sure I switch to the correct version of the docs, then find the documentation for the thing I'm trying to use. In my ideal world the JSDoc comments would serve as a sort of source of truth from which the documentation website would be derived, but that's probably a big ask.

Instead I'd just ask that more of the information available in the docs could be also made available in JSDoc comments and/or have JSDoc comments linking back to the official docs:

/**
 * @deprecated - use `structuralSharing` instead
 * @see https://tanstack.com/query/v4/docs/react/reference/useQuery#options-isDataEqual
 */
isDataEqual?: (oldData: TData | undefined, newData: TData) => boolean

Side request: provide more anchors/ids for parts of the docs so we can link directly to stuff like the QueryOptions.isDataEqual instead of only being able to link to useQuery and then ask the person to search for "isDataEqual".

[TkDodo]

yeah absolutely. If you want, please contribute this?