fix(ui): make Authorize version-aware for OCPP 2.0.1 stations

fix(ui): make Authorize version-aware for OCPP 2.0.1 stations

Extract shared OCPP version-aware payload builders into
ui-common/src/utils/payloadBuilders.ts (buildAuthorizePayload,
buildStartTransactionPayload, buildStopTransactionPayload, isOCPP20x,
buildIdToken) and consume them from both Web UI and CLI.

The Web UI Authorize was always sending flat { idTag } regardless of
OCPP version, causing "Request PDU is invalid" on OCPP 2.0.1 stations
which require { idToken: { idToken, type } }.

Closes #1817