Bring F3 up to K2 on its release branch (part 3 of 3)

testdata/store-tests holds both sides' entries; F3's own sit beside each other, so the list merges with the release branch's.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

internal/link/build.go

@@ -358,6 +358,12 @@ type BuildResult struct {
 	ReusedFrom *ReusedFrom `json:"reused-from,omitempty"`
 	BuiltWhy   string      `json:"built-why,omitempty"`
 
+	// Predefined is the list of predefined keys at the root of the repository at the commit built (novox/hq ADR
+	// 0348 §7), which the manifest was judged against: the controller publishes the catalogue's from a trunk
+	// build, the newest by Generation winning. Absent for a repository holding none, and from a builder that
+	// predates the list.
+	Predefined *PredefinedList `json:"predefined,omitempty"`
+
 	// Source is the request's, echoed: the seat form of the repository, for whoever registers.
 	Source *SourceOnSeat `json:"source,omitempty"`
 
@@ -370,6 +376,14 @@ type BuildResult struct {
 	Checked *CheckRequest `json:"check,omitempty"`
 }
 
+// PredefinedList is the list of predefined keys a build read (novox/hq ADR 0348 §7): Keys its canonical text, a
+// JSON object of keys, and Generation how many commits the commit built stands on — of two commits on one trunk
+// the later has more, which is what orders two builds' lists; 0 when the builder could not say.
+type PredefinedList struct {
+	Keys       json.RawMessage `json:"keys"`
+	Generation int             `json:"generation,omitempty"`
+}
+
 // ReadRepository is a repository a build read source from besides the module's own, at the branch,
 // tag or commit it read. Spelled here as well as in the catalogue and the inventory, for the reason
 // MadeArtifact is: one direction of dependency.