Jay Hickey 7e9be3c28c Update gog Calendar command date format to RFC3339 ...

I am seeing instances where Clawdis is not including timezone in the gog calendar range requests. This results in a 400 bad request from the Google API, e.g.

```
gog calendar events primary --from 2026-01-02T00:00:00 --to 2026-01-03T23:59:59 --account <email>

Google API error (400 badRequest): Bad Request
```

While this is a valid ISO 8601 format, Google Calendar API requires a stricter RFC 3339 format like the following:

```
gog calendar events primary --from 2026-01-02T00:00:00Z --to 2026-01-03T23:59:59Z --account <email>

<calendar events listed successfully>
```

2026-01-03 02:30:32 +01:00

..

SKILL.md

Update gog Calendar command date format to RFC3339

2026-01-03 02:30:32 +01:00