v2.12.0 — the app looks for new versions, the UK record says when its data took effect

The desktop app now looks for new versions, and the UK airspace record says when its data took effect.

A polish release shaped by two sources: the field tester who has been
running the desktop app and the 360° editor hard since v2.9.0, and a
closer read of what the UK airspace dataset actually publishes. Nothing
here changes what the tool does with your footage; everything here makes
it say more clearly what it knows, and how it knows it.

The app tells you when a new version exists (#319)

• On launch the desktop app asks, once, whether it may look for new
  versions. Say yes and it checks at most once a day; say no and it
  never asks again. The check is one request to pypi.org for the latest
  version number - nothing about you or your files is sent, and the app
  never downloads anything on its own. When a newer version exists a
  quiet line appears in the footer with a link to the release page.
• The app grows no setting of its own for this: it reuses the consent
  dji-embed doctor --online / --offline already keeps, so the CLI
  and the app always agree. For the machine contract, doctor --progress jsonl now reports that consent as summary.update_check and only
  goes online on the explicit --online flag, never as a side effect.

UK airspace: cycle date and activation text (#502, #503)

• The UK record now states the AIRAC cycle date its dataset took effect
  ("Effective 2026-08-06") beside the time it was fetched, so a reader
  can tell "old copy" from "current cycle" at a glance. Records built
  from copies cached before this release simply omit the line; nothing
  is refetched.
• Many UK danger areas are part-time, and the dataset carries their
  published activation status and schedule text ("available for
  activation - Mon-Sat SR to SS"). That text now travels into every zone
  popup, 2D and 3D, and into the flight record's zone table, clearly
  labelled as published and not evaluated: the record still treats the
  zone as applicable, because the AIP and NOTAM service hold the
  authoritative hours, not this tool.

Field-tester round (#530, #531, #532)

• The flight map's Airspace zones option now works together with
  the 3D terrain map toggle in the desktop app; the CLI has rendered
  published ceilings as translucent volumes since v2.7.0, and the app
  had quietly dropped the flag (#530).
• When a 360° save times out, the error now quotes the measured elapsed
  time and the ExifTool version, and the desktop app keeps a small
  rolling helper.log of everything its helper processes print
  (capped around 1 MB), so the next slow-disk or antivirus report
  arrives with numbers instead of guesses. The troubleshooting guide
  gained the matching isolation playbook (#531).
• Seven small things from the same tester (#532): the app version in
  the title bar; the hover preview no longer lingers under a clicked
  pin's popup; the popup thumbnail says it opens the 360° viewer; the
  view editor's film strip ellipsizes long names, keeps the active
  chip in sight and pages with large arrows; wheel zoom in the editor
  moves half as far per notch; Edit at full resolution in the
  360° views options (the CLI's --max-width 0); and the large-
  panorama notice on the photomap now says plainly that it is your
  graphics card, not the map, that has the limit.

Maps at scale (#515)

• A combined dji-embed map of many flights no longer grows a legend
  taller than the screen: past ten rows the layer control collapses
  and opens on hover. Folders with tracks but no photos no longer show
  a hover-preview toggle with nothing to preview.

What's Changed

• 📝 Auto-generate changelog for v2.11.0 by @github-actions[bot] in #528
• docs: catch the overview docs up with v2.11 (airspace, map, panoedit, 360° views) by @CallMarcus in #529
• fix(gui): let --airspace through with the 3D toggle (#530) by @CallMarcus in #533
• fix(panoedit/gui): stop discarding the save-timeout evidence (#531) by @CallMarcus in #534
• polish(gui/panoedit/photomap): the v2.9.0 field-tester round (#532) by @CallMarcus in #535
• feat(geo): state the AIRAC cycle date in the UK airspace source line (#502) by @CallMarcus in #536
• feat(geo): render UK activation status and schedule text in zone popups (#503) by @CallMarcus in #537
• polish(geo): collapse the combined map's legend at scale, drop the hover toggle on photo-less maps (#515) by @CallMarcus in #538
• feat(gui): launch update note reusing doctor's opt-in online check (#319) by @CallMarcus in #539
• release: prepare version 2.12.0 by @CallMarcus in #540

Full Changelog: v2.11.0...v2.12.0