Probe Gemini CLI skill calls with working credentials and enable completion if they pass #490

Parent

#454

What to build

Found while #459 was delivered. Gemini CLI finds Agent Skills but its probe could not reach a model on the test Mac (expired OAuth, suspended API key project), so Gemini stays Invocation Style none (ADR 0010). With working Gemini credentials, run the probe skill through the New Agent launch path at the prompt start and in the middle; if a position passes, fill in Gemini's Invocation Style and position and enable completion.

Waits on: a working Gemini credential on the test machine (a browser sign-in to gemini, or a valid GEMINI_API_KEY). Move to Todo when it exists.

Acceptance criteria

• Probe evidence at both positions through New Agent with a model response.
• Gemini's Skill Location is filled in when a position passes; otherwise it stays none with the reason.
• The design doc records the result.

Blocked by

• Verify skill completion end to end and merge it to main #460