- Add 'state' field to all 139 activity entries in activities.yaml
- Songs: state shows artist (e.g. 'by kz (livetune)')
- Games: state shows genre (e.g. 'Rhythm Game', 'Sandbox', 'FPS')
- Update pick_activity_for_mood() to return 3-tuple (type, name, state)
- Update update_bot_presence() to pass state to discord.Activity()
- Add state validation in set_activities_for_mood() (optional string)
- Update Web UI editor: view shows state, edit form has state input
- State is fully optional — backward compatible, no breaking changes
The 'state' field appears as a secondary text line in Discord profile
popup, the richest display possible for bot accounts (full Rich Presence
with cover art/buttons is server-side restricted to OAuth applications).
Curated list of Vocaloid/Miku songs and real game titles for each
normal mood (13 moods, excluding asleep) and each evil mood (10 moods).
Each entry has type (listening/playing), name, and weight for
weighted random selection. Editable via this file or the Web UI.
