`createMission`, `updateMission`, and `{start,finish}Iteration` all
received caller-supplied objects that can be Svelte 5 \$state Proxies
(MissionInputPicker binds the inputs array with \$state). IndexedDB's
structured-clone algorithm doesn't accept proxied arrays and throws
`DataCloneError: [object Array] could not be cloned` — visible to
users as "Mission anlegen" failing silently after clicking Create.
Wrap each proxy-carrying payload in `structuredClone()` at the store
boundary:
- createMission: `inputs` + `cadence`
- updateMission: whole `patch` (anything can be proxy)
- startIteration: `plan`
- finishIteration: `plan` (conditional)
`structuredClone` is the native browser / Bun helper; strips Proxies
while preserving Dates / Maps / Sets / nested plain data. Store stays
robust to any future caller that forgets to snapshot before passing.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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