The bundled @omniroute/opencode-plugin registers its provider under
'opencode-omniroute' (the 'opencode-' prefix is required by OpenCode
>=1.17.8's native-adapter gate on model providerID). But the CLI
instructed 'opencode auth login --provider omniroute' — the unprefixed
id — so OpenCode reported 'Unknown provider "omniroute"' because it
resolves --provider against the exact provider id the plugin registered.
Add resolveOpenCodeAuthProviderId() helper that idempotently adds the
'opencode-' prefix when absent, and use it everywhere the CLI builds
or prints the --provider argument: resolveOpenCodeAuthSpawn args,
runOpenCodeAuth ENOENT message, and runSetupOpenCodeCommand 'Run
manually'/'Next step' messages. Update the plugin README and test
assertions to match.
Co-authored-by: diegosouzapw <diegosouzapw@users.noreply.github.com>
904e8af09a