CapxulProvider reference

CapxulProvider requires exactly one bootstrap mode.

Prop	Mode	Meaning
`publishableKey: string`	created client	required bootstrap credential
`client: CapxulClient`	injected client	caller-owned, already-created client
`requirement?`	created client	`none`, `counterfactual`, or `deployed` readiness target
`signer?`	created client	optional consumer-held deployment signer
`observation?`	created client	host-owned SDK failure observation adapter
`queryClient?`	both	TanStack cache pinned at mount
`children`	both	React subtree receiving both contexts

Created-client mode calls createCapxulClient, exposes bootstrap status, and closes the created client on teardown or re-bootstrap. Injected-client mode is ready immediately and leaves disposal with the caller.

useCapxul() returns:

type CapxulBootstrapStatus = "bootstrapping" | "ready" | "error";

interface CapxulBootstrapState {
  status: CapxulBootstrapStatus;
  error: CapxulError | null;
  retry(): void;
}