Use when building or debugging a browser-based CTI softphone adapter using the Salesforce Open CTI JavaScript API — covers callcenter.xml definition, Lightning utility item registration, core API methods (enableClickToDial, onClickToDial, screenPop, setSoftphonePanelHeight, saveLog), call logging as Task, and the lightning-click-to-dial LWC component. NOT for Service Cloud Voice Amazon Connect setup, Omni-Channel routing configuration, or CTI adapter AppExchange package selection.