Skill Sync only worked against a Nous Portal sync plane that was never made
publicly accessible, so no install has ever used it. We don't want it in core
right now, so this deletes it outright instead of moving it behind a plugin
hook surface nobody needs yet:
- `hermes sync` command, `tools/skills_sync_client*.py` and their tests
- the personal pull ticks (gateway housekeeping, classic CLI startup,
`hermes serve` maintenance) and the debounced post-write push
- the per-skill `sync` usage flag (`set_sync` / `is_sync_enabled`)
- the `skills/_org/<org_id>/` mirror: index gating on `.active_org`, the
`[org-shared]` / name-collision labels, the org provenance header and
`org_provenance` field on skill_view, the org delete guard and the
auto-propose `org_sharing` note on skill_manage
The code is preserved in the private NousResearch/hermes-skill-sync repo if
the feature comes back.
64ad33e32d