fix(actionbar): preserve cooldown state across relog

[blakinio]

Purpose

Repair the confirmed action-bar cooldown lifecycle defect where protocol cooldown packets can be missed or erased before UI construction, visual preferences suppress cache updates, and button rebuilds stop restored overlays.

Task

• Task: OTC-20260726-actionbar-cooldown-lifecycle
• Task record: docs/agents/tasks/active/OTC-20260726-actionbar-cooldown-lifecycle.md
• Dependency: PR fix(entergame): recreate character list after relog #31 character-list lifecycle repair

Scope

• module-lifetime cooldown subscriptions
• synchronous session cache reset at correct boundaries
• cache-first packet handling independent of visual options
• maximum individual/group remaining-time restoration
• common restoration path for text spells, runes and multi-actions
• focused Lua lifecycle tests

Safety

• no protocol payload, Canary, hotkey mapping or persisted action schema changes
• existing ActionBarController and widgets remain authoritative
• draft until dependencies, exact-head CTest and required Windows CI pass