Read what a node was sent from its assignment keys; a pulled-in module keeps a standing key; a hand send is a time (issue 1109)

SentBuilds answers from the keys of the node's assignments that name a commit, known when the node was sent anything and no key says its commit unknown. A send that names its builds writes the commit, build and rollout on each carried module's key (a module nothing assigns gets a standing key marked pulled-in, never a state) and clears what every other key of the node named; a send by hand writes sent-unknown, a time, on every key and clears their commits. A failed write of these fails the record of the send. node.sent_builds is no longer written. The plan pass ends a pulled-in key only when no send carries it.

internal/chain/records.go

@@ -196,6 +196,14 @@ type Assignment struct {
 	// Pending is the assignment's wait for its build (novox/hq ADR 0261), kept in the value of the key it waits for and, when
 	// it is made, carried into the value that stands: the record of what became of the wait.
 	Pending *Pending `json:"pending,omitempty"`
+
+	// PulledIn marks a standing value of a module that is on the machine only because another requires it, or because a
+	// send carried it: no time assigned, but a key all the same, so what the machine was sent of it is kept and read
+	// (issue 1109). Never a state: every reader treats a non-empty state as no assignment, and would take it off the machine.
+	PulledIn bool `json:"pulled-in,omitempty"`
+	// SentUnknown is when a send by hand made what the machine runs unknown (a declaration sent with no builds known): the
+	// commit is cleared with it. Absent normally; a send that names its builds clears it.
+	SentUnknown time.Time `json:"sent-unknown,omitzero"`
 }
 
 // StatePending is the State of a value that holds no assignment but a pending one.