The Install/Unlink/Link/LinkAuto Varlink methods always auto-discover the ESP and XBOOTLDR partitions and Install always runs make-entry-directory in auto mode, so IPC callers cannot match what the CLI verbs do with `--esp-path`, `--boot-path` and `--make-entry-directory`. Add optional `espPath`, `xbootldrPath` and `makeEntryDirectory` parameters that feed into the same code paths the CLI already uses.