fix(forge): cancel stale scheduled callbacks

[blakinio]

Purpose

Repair Forge lifecycle races where scheduled Lua callbacks survive window/controller teardown and C++ later attempts to invoke expired functions.

Task

• Task: OTC-20260726-forge-scheduled-events
• Task record: docs/agents/tasks/active/OTC-20260726-forge-scheduled-events.md
• Dependency: PR fix(wheel): align ConvictionBonus summary indices #34 Wheel conviction repair

Scope

• retained event-handle registry
• generation guards for queue/cancellation races
• cancellation before hide, game end and terminate cleanup
• focused repeated-lifecycle Lua tests

Safety

• no Forge protocol, pricing, convergence or animation-timing changes
• only module-owned scheduled callbacks are tracked
• draft until dependencies and exact-head required CI pass