Review residuals #5/#7/#8/#11/#12 + #3 wiring: forward the configured GitHub
token to the abandon route's client; guard abandon against finalized/merged
groups; reconcile an open group PR's state from GitHub on single-group reads
(merged out-of-band now flips prState); add fn branch-group abandon for
agent-native parity; block branchName shell injection (execFile argv push +
core-side branch-name validation at group creation); and collapse the
branch-groups list N+1 to a single task fetch via a shared
filterTasksByBranchGroup helper.
e54417c987