Deterministic logic sequencing

Foundation capability (taktora-executor v0.1): items compose into chains and DAGs with explicit ordering and abort semantics — the structural equivalent of a PLC cause-effect network.

Feature: Deterministic logic sequencing FEAT_0013
status: open
satisfies: FEAT_0010
is satisfied by: REQ_0020, REQ_0021, REQ_0022, REQ_0023
is implemented by: BB_0027

Items compose into chains and DAGs with explicit ordering and abort semantics — the structural equivalent of a PLC cause-effect network.
Requirement: Sequential chain execution REQ_0020
status: implemented
satisfies: FEAT_0013
is verified by: TEST_0114
links outgoing: BB_0027, TEST_0114

The runtime shall execute the items of a chain in declared order on a single dispatch slot per chain invocation.
Requirement: Parallel DAG execution REQ_0021
status: implemented
satisfies: FEAT_0013
is verified by: TEST_0115
links outgoing: BB_0027, TEST_0115

The runtime shall execute the vertices of a DAG concurrently when their in-edges are all satisfied, and shall block downstream vertices until all of their upstream vertices have completed.
Requirement: Abort propagation REQ_0022
status: implemented
satisfies: FEAT_0013
is verified by: TEST_0116
links outgoing: BB_0027, TEST_0116

An item returning Ok(ControlFlow::StopChain) or Err shall prevent any downstream items in its enclosing chain or DAG from being dispatched within the same triggering cycle.
Requirement: Conditional inclusion REQ_0023
status: implemented
satisfies: FEAT_0013
is verified by: TEST_0117
links outgoing: BB_0027, TEST_0117

The runtime shall provide a wrap_with_condition(item, predicate) helper that gates an item’s execution on a runtime-evaluated predicate.