Kind 2 (cell-task wave chain): a new cell-task under root-subtask UT_n
depends on every cell-task under every root-subtask in UT_n.dependency_ids
(the kind-1 wave-chain edges), so its branch carries the previous wave's
merged cell work. Re-derived from the root-subtask's deps, not the cell-task's
own dependency_ids (which also carry UX/product-fanout edges the by-osmosis
edge must not pick up). A root may fan to several cell-tasks (different cells),
so the previous wave's cell-task is a SET.
Kind 4 (by-osmosis): the first dev task (sequence 0) under a cell-task depends
on each predecessor cell-task's tail (max-sequence) dev task, so the new wave's
first branch carries the previous wave's fully-merged tail. Subsequent dev
tasks inherit the tail via kind 3 or the merged base.
Both wired from _create_subtask_from_inputs, dispatched on parent.team
(MAIN_PM -> kind 2; cell team -> kind 4). Pure helpers
(cell_task_wave_chain_depends_on, by_osmosis_tail_dev_tasks) unit-tested in
test_sequencing.py; TaskService methods integration-tested. Idempotent +
best-effort throughout (add_dependency dedupes; missing predecessors are
no-ops). Also fixes a latent mypy-tests gap (estimated_complexity required on
direct TaskCreateRequest calls in the S2 tests).
Renn F
9927d248ea