astronomy_get_satellite_passes

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Predict visible passes of a satellite (e.g. the ISS, NORAD 25544) over an observer in the next `days`. Identify the satellite by exactly one of `norad_id` or `name` — supplying both, or neither, is rejected. `name` is matched as a case-insensitive substring of CelesTrak's catalog names, so it resolves only when it picks out a single object: a broader query comes back with the matching objects and their catalog numbers to choose from, and the result echoes the query that resolved it as `resolved_from_name`. Fetches the object's current GP element set from CelesTrak, propagates it with SGP4 in-process, and returns each pass's rise, peak, and set times with azimuths and the peak elevation. Only passes that are naked-eye-plausible are returned — the satellite must be sunlit at peak while the observer's sky is dark. Every returned pass rises within the requested window: a pass already underway at `start` is omitted rather than reported with `start` as its rise, so back up `start` to see it. A `start` further than about a month from the element set's epoch is rejected as out of range on that distance alone, and an element set that will not propagate to a window inside that horizon is rejected as a reentry — so an empty `passes` means only that nothing was visible. CelesTrak publishes only current element sets, so in practice `start` must be within about a month of today. NORAD catalog numbers and catalog names are found at celestrak.org or heavens-above.com. This is a gated, network-backed extension (CelesTrak is keyless but rate-limited; element sets are cached briefly). Default elevation 0 m; pass an IANA timezone for observer-local pass times.