Add Map StartPos column type

[burnhamrobertp]

Adds a graphical editor for the maps table's startPos column, in the same spirit as the startbox editor. You place and name start positions on the minimap (drag to move, click a marker to rename / set coords / delete), and per team configuration assign each spawn to a team with a role and optional base center. Configs (1v1, 4v4, 8v8, ...) are read from the data and you can add or remove them. Markers approximate the in-game start circles (radius and label sizes taken from map_start_position_suggestions.lua), and there's a raw-JSON view in the editor for copy/paste. Edits auto-save.

It's a single column that should work as an in-place replacement for the JSON column presently in place. It uses some of the same configurability as what the startboxes column has but didn't require a subtable, since a startPos value is one document with shared named positions that every config references. The stored value stays a Firestore map - the same shape as the current JSON column - so update_from_rowy reads it unchanged.

Assisted by Claude Opus 4.8

[burnhamrobertp]

[p2004a]

Edits auto-save.

And there is no undo, if you misclick something, just want to play with the thing, you accidentally modified the data.

This is exactly why the startbox editor doesn't do auto save and save is explicit action.

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This doesn't show whole map, it's cut

startbox editor handles this correctly, in both X and Y coordinates.

This alignment is then also problematic when modifying the map in full screen, map doesn't fill the screen properly:

Being able to zoom-in/zoom-out to be able to place the elements precisely was a requirement and why https://files.p2004a.com/startpos-editor/ has this functionality

[burnhamrobertp]

The more I got into the UX the more I saw how it could be improved, in addition to the issues you pointed out.