Remove core's local proto/ fork and pull the canonical block/proto repo in
as a submodule at the same path. buf.yaml now sources from the submodule's
orchestrator/v1 namespace; everything outside that (blockninja, helpdesk)
is excluded from generation.
This brings the orchestrator's local-only RPCs (PluginScopeService.ListMyPlugins,
PluginRegistryService.SubmitForReview, the full PluginModerationService) into
core's bindings — harmless surface area for the CLI, prerequisite for the
orchestrator to also stop forking the proto.
Side effect: the CLI's account picker now uses the canonical
AccountService.ListMyAccounts in accounts.proto rather than the duplicate
PluginAuthService.ListMyAccounts that lived only in core's fork. The
existing Account message uses Name (no DisplayName / Role), so the picker
output collapses to "slug — Name".
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>