Auto-assignment (no real id known: a manual add, or an accepted
proposal with no confident marker-id read) must stay visually
distinct from a genuinely detected id, or a made-up number could
collide with or be mistaken for a real one. Reverts the previous
commit's switch to numeric auto-assignment (_next_free_numeric_id) --
that was wrong, caught by the user immediately. _next_free_id
(letters, rolling over to "AA"/"AB"/... past 26) is back as the
fallback, still scoped per type (that part of the previous change was
correct and stays). Plain numbers are reserved for an id
_accept_proposal is actually confident was read off the marker itself
(Proposal.detected_id), passed straight through and never touching
auto-assignment.
Also fixes detected_id's own collision pre-check in _accept_proposal,
which wasn't scoped per type either -- same bug as the Change ID
popover fix, just in a second place: a detected id could get
needlessly discarded because an unrelated type already used that
number, not because of a real collision.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Dominik Roth
5a35ea7776