languageClient

The LanguageClient the consumer registers as the client side of their transport (e.g. ksrpc's connectAsLspClient).

Deviation from upstream: as with server, the transport lives in the consumer's code rather than in this module. By handing the consumer this LanguageClient, server→client notifications — most importantly textDocument/publishDiagnostics — are routed back into the editor: the handler resolves the file/session via the workspace and pushes diagnostics into :lint (see serverDiagnostics). Other server→client methods have spec-safe defaults until later feature issues fill them in.