fusion/.changeset/FN-5060-extend-duplicate-guard.md

@runfusion/fusion

@runfusion/fusion
patch

Extend the FN-4918 deterministic duplicate guard to the remaining task-creation surfaces: CLI fn task add (direct-store, with a new --no-dedup flag), engine createAgentTask (powers fn_task_create and triage subtask splits — duplicate detections now report Linked existing ...), and mission feature triage (links to the canonical task on duplicate). Dashboard POST /api/tasks now consumes the same shared helper so behavior is identical across surfaces. InlineCreateCard gains the duplicate-warning modal already shipped on QuickEntryBox.