Register on the fingerprint, not the commit; count the take-in's attempts as settled (issue 1945, ADR 0544, review 3)

registeredAt compared commits, so a catalogue merge that moved only the commit
(2df05030 at 18:02, a85d9037 before it) took every catalogue module in again
and composed it: about 200 take-ins, some 25 minutes, on every mesh-catalog
merge, which held nextcloud for an hour. A module whose trunk fingerprint is
the one it is registered at now has the new commit recorded (built_from and
source_head, as a registration moves them) and composes nothing unless its
composition or grant is missing. Readers of the registered commit: the
fingerprints read the commit's build or, with none, the indexer's value at it,
which names the same fingerprint; status, modules, the board and the facts
read it as the source's commit, which it is; the upgrade path counts it as
built from that commit, which it is.

The stall watch counted only settles the bus accepted, so each refused
acknowledgement at a first start left work held for good: it now counts the
loop's every attempt. The acknowledgement and refusals at the stop are sent
past the stop, and the connection closes only after the readers and the loop
have ended.
Research 072: the take-ins on a bounded pull consumer.

internal/inventory/catalogue.go

@@ -210,6 +210,21 @@ func (i *Inventory) hasModule(ctx context.Context, name string) (bool, error) {
 // This is the whole of noticing. Nothing here builds anything — it writes down that the two
 // halves differ, which is what makes *is this current?* answerable without building, and what
 // makes a module that nobody rebuilt visible rather than silent.
+// RecordBuiltFrom records that a registered module stands at commit, its manifest and fingerprint unchanged: a catalogue
+// merge that left its sources alone (novox/hq ADR 0544 §3). The head moves with it, as a registration moves it; the
+// module's builds and manifest stay as they are.
+func (i *Inventory) RecordBuiltFrom(ctx context.Context, module, commit string) error {
+	tag, err := i.store.Pool().Exec(ctx,
+		`update module set built_from = $2, source_head = $2 where name = $1`, module, commit)
+	if err != nil {
+		return fmt.Errorf("cannot record %s at %s: %w", module, commit, err)
+	}
+	if tag.RowsAffected() == 0 {
+		return fmt.Errorf("%w: %s", ErrNoSuchModule, module)
+	}
+	return nil
+}
+
 func (i *Inventory) SourceMoved(ctx context.Context, module, head string) error {
 	tag, err := i.store.Pool().Exec(ctx,
 		`update module set source_head = $2, source_seen = now() where name = $1`, module, head)