Sunspill 0.2.0

A room set up on a phone in a few minutes, and a way to check it against the sun you saw.

• Guided setup. Seven steps: address, room, windows and doors, which way it faces, what stands around, furniture, and a check against the real sun. Built for a phone, with large touch targets, and it works on a desktop too.
• Address and map. Search an address or drop a pin on an OpenStreetMap map. Latitude, longitude and time zone fill in. All three online services (address search, map pictures, building outlines) are off until allowed, say what they send, and can be switched off again. See docs/PRIVACY.md.
• Facing. Turn the room over the outline of your building, press one button to line the window wall up with a wall of that building, or read the phone compass with the World Magnetic Model declination added. Averages the reading and waits until it is steady.
• Rooms. Seven typical rooms to start from, a trace of a floor plan or listing photo with a two point scale, real lengths drawn along the walls, snapping, doors, balconies with a rail, floors, and furniture that can be turned and snaps to walls and neighbours. A shelf is new.
• Surroundings. Buildings and their heights from OpenStreetMap, with guessed heights marked and editable, trees, and buildings you add. Outlines of any shape. Switch each one off to see what it costs in hours of sun. A clock on the map moves a dotted line toward the sun and outlines in orange the buildings that shade a window at that time.
• Check mode. Mark the sun patch you saw on the floor, or lay a photo of the floor under the plan. See the overlap and offset, and fit the facing and the window to your marks.
• Validation. Every geometry piece is compared with an independent reference: pvlib and shapely for the shadows, pygeomag, pyproj, timezonefinder and OpenCV for the rest. 0 disagreements in 54,000 shadow probes. docs/ACCURACY.md shows how much each wrong input moves the patch.
• Kept on your device. The last room you edited comes back when you open the page without a link. "Start over" in the Share tab forgets it.
• Sharing. A new link format (r2) that carries buildings, floors, balconies and observations. Old links still open. "Hide my exact location" also drops building names.
• Install on a phone. A web manifest and icons, so "Add to Home Screen" opens the page full screen.
• Library. New exports for obstacles, geography, declination, the compass, fitting and tracing.
• Fixed. A sun running exactly along a wall no longer lights it. An outline that crosses itself no longer disappears. A latitude and longitude typed in another time zone bring that zone along. A friend's link that you edit no longer replaces your own room: yours is set aside and "Bring back my earlier room" in the Share tab returns it. Closing the setup with corners marked but not saved asks first. Moving the room to a new place says that the buildings loaded for the old one were removed. Text boxes are 16 pixels high on a phone, which stops Safari on an iPhone from zooming in when one gets the focus, and a 320 pixel wide screen no longer pushes the Undo button or the three buttons of the Share tab out of view.