- Deleted scripts/hud.js, scripts/event-translation.js, styles/hud.css,
templates/hud.html.
- Removed mod.api.getHud/openHud/closeHud/buildHudUpdatePayload exports.
- Removed hudPosition setting (moved to combat-hud-hub).
- Added hub integration: at ready, if combat-hud-hub is installed,
register a 'pinned-achievements' section. The chatBubble listener
now also pushes entries into that section via hub.api.pushFeedEntry.
- Soft-dep on combat-hud-hub (optional); popover still works without
the hub.
- Tests: 57/57 passing covering sections A-G (rule engine, catalog,
awarding, hooks wiring, hub integration, graceful degradation).