Each tag gets a stable code (01-99) assigned by the server and stored in
tags.json; existing tags get one when the file is loaded. A fixed-width
Filters column shows the codes of the active tags found in each message
(room for 3, then 2 + "+N", all listed in the tooltip).
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>