Issue #3614447: Let the token name the payment its step is waiting on, and let the step name the kind

Follows [#3614434], which took the payment vocabulary out of kessai. orchestra_payment no longer compiled against it, and the reason it used the constant was worth fixing rather than translating.

The conflation. A payment's orchestra_token field said both "this payment belongs to this run" (what the run-end cleanups need, and why a consumer pins its own payments there) and "this is the payment the parked step is waiting on". One value, two questions, so the bridge needed a second test to tell a step's own payment from anything else in the run, and that test was a kind comparison.

The fix. The token records the payment it awaits. Only a settlement of that payment resumes the step; the payment's own pin goes back to meaning run membership alone. PaymentWorkflowBridge and PinnedPayment compare no kind at all, and the step gains a payment_kind setting (step_payment by default, validated as a machine name) so a workflow whose domain has its own word for the payment says so and kessai stores it without reading it.

TokenStorageSchema gains the indexes() seam kessai's payment schema already offers, and the bridge uses it: it now asks which token awaits a payment on every payment event the site raises, which would otherwise scan the engine's hottest table.

Tests: the six orchestra_payment kernel classes pass. The one that matters is PaymentBridgeTest::testOtherPaymentInTheRunDoesNotResume, which authorizes a guarantee pinned to the run while a step is parked. Pointing the bridge back at the payment's run pin was measured to fail it, so it discriminates the fix from the naive translation rather than ratifying it. PaymentIndexTest now asserts all four indexes, both owning modules' included.

Docs and the French translation are in the same commit. Both projects are pre-1.0 and reinstall-only, so nothing migrates: a run parked on a payment step at upgrade time has to be re-run.

CI cannot go green until [#3614434] reaches 1.x-dev on packages.drupal.org, since the current dev release still ships the removed constants.