v0.10.0 — /outstanding-tickets skill + scope discipline

Added

• /outstanding-tickets skill — answers "what's outstanding" with a single token-cheap ticketgraph list --status outstanding call and stops. The first of a planned set of command-wrapper skills; dogfoods the project's token-efficiency pitch.

Changed

• ticketgraph skill — new "Common mistakes" entry: a status/list question is one list call. Don't pile on stats / blockers_of / version checks unless the user asks "why blocked", wants counts, or wants per-ticket detail.