Post-implementation /simplify cleanup. Registers the plan-specified
process.on('exit', killAllProcesses) safety hook in index.ts (was missing —
closes an orphan-subprocess gap on hard exit). Removes the unwired idle-timer
(engine StuckTaskDetector + dispose()/registry teardown is authoritative per
KTD4a) and its tests. Fixes a stale dispositionFor doc comment, removes a
redundant identifier re-normalization in the event bridge, and clarifies why
the FusionCategory type keeps git_write/task_agent_mutation. Behavior-
preserving; 177 tests green.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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