* feat(chat): add message fork action
Use a Y-shaped repo-forked icon in fork UI and expose the current-tail /fork action in the last message meta action row instead of the input toolbar. Keep terminal fork commands out of optimistic run/thinking state so no model activity is implied.
* fix(chat): debounce fork message action
* fix chat session click after fork
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Co-authored-by: Zhicheng Han <zhicheng.han@mathematik.uni-goettingen.de>
* feat: add local chat fork command
* docs: add chat chain fragment for fork command
* feat(chat): persist fork point metadata
Record the copied child message that marks the fork boundary and surface it through resume/session client state.
* feat(chat): show fork timeline divider
Render fork lineage inline after the copied fork point and link back to the original session with in-app switching.
* fix(chat): use branch title and trim fork divider
Default fork titles now use branch: <original title>; the fork divider uses a branch icon and relies on the parent title link instead of a duplicate view-original button.
* fix(chat): preserve fork divider hydration metadata
* test(chat): accept fork command alias in registry contract
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Co-authored-by: ekko <152005280+EKKOLearnAI@users.noreply.github.com>
ekko