* feat(server): add OPENCODE_HOST env var for external OpenCode connections Allows specifying a full base URL (e.g. https://hostname:4096) for external OpenCode connections, supporting custom hostnames and HTTPS. When set, OPENCODE_HOST overrides OPENCODE_PORT. Malformed values are fatal at startup. * docs: document OPENCODE_HOST env var in README and AGENTS * Fatal error when OPENCODE_HOST has path, search or hash Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com> Signed-off-by: Colin Mollenhour <colin@mollenhour.com> * fix(server): use external origin when re-probing OpenCode --------- Signed-off-by: Colin Mollenhour <colin@mollenhour.com> Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>