feat(ocpp-server): enhance OCPP 2.0.1 mock server for comprehensive E2E testing ...

feat(ocpp-server): enhance OCPP 2.0.1 mock server for comprehensive E2E testing (#1752)

* feat(ocpp-server): add boot status sequence for Pending→Accepted transition testing

* feat(ocpp-server): add configurable TriggerMessage type

* feat(ocpp-server): add configurable Reset type and ChangeAvailability status

* feat(ocpp-server): add command sequencing for multi-step CSMS workflows

* feat(ocpp-server): add groupIdToken and cacheExpiry to Authorize response

* feat(ocpp-server): add multi-variable SetVariables/GetVariables CLI support

* fix(ocpp-server): share boot_index across reconnections so sequence advances correctly

* fix(ocpp-server): schedule send_commands as background task so it runs after cp.start()

* fix(ocpp-server): correct CLI help text casing and validate boot-status-sequence

* chore: remove E2E test plan from PR branch

* refactor(ocpp-server): fix misplaced tests and harmonize style

* docs(ocpp-server): document all new CLI flags and transaction tracking

* fix(ocpp-server): harden input validation and connection cleanup

* fix(ocpp-server): clean up auth-mode choices and CLI edge cases

* fix(ocpp-server): validate cache-expiry, skip trailing commas, document yield semantics

* fix(ocpp-server): harmonize empty-entry handling and wrap CLI parsers in error handler