fix(artifact): bound authoritative publication paging

Unchanged folder exchanges must not pay archive-sized costs merely to compare transport state, and changed exchanges must remain resumable within fixed work budgets as publication history grows. Read the authoritative checkpoint head first, page its publication ledger by a durable keyset cursor, and verify each page against the recorded revision before exposing dependencies.\n\nRemote provider URIs are not local filesystem roots, so exclude recognized S3 sources from folder-overlap protection before path canonicalization.

Author: wesm

cmd/agentsview/artifact_sync.go

@@ -207,6 +207,9 @@ func artifactSyncForbiddenRoots(appCfg config.Config) []string {
 		if strings.TrimSpace(root) == "" {
 			return
 		}
+		if isRemoteSourceRoot(root) {
+			return
+		}
 		root = filepath.Clean(root)
 		if _, ok := seen[root]; ok {
 			return

cmd/agentsview/artifact_sync_test.go

@@ -61,8 +61,12 @@ func TestRunArtifactFolderSyncPassesOnlyDistinctProtectedRoots(t *testing.T) {
 	appCfg := config.Config{
 		DataDir: dataDir,
 		AgentDirs: map[parser.AgentType][]string{
-			parser.AgentClaude: {providerA, filepath.Join(providerA, ".")},
-			parser.AgentCodex:  {providerB},
+			parser.AgentClaude: {
+				providerA,
+				filepath.Join(providerA, "."),
+				"s3://archive-bucket/claude",
+			},
+			parser.AgentCodex:  {providerB, "s3://archive-bucket/codex"},
 			parser.AgentGemini: {dataDir},
 		},
 	}

internal/artifact/transport_folder.go

@@ -56,12 +56,12 @@ type folderTransport struct {
 }
 
 type folderPushCursor struct {
-	Generation    string `json:"generation,omitempty"`
-	Origin        string `json:"origin,omitempty"`
-	KindIndex     int    `json:"kind_index,omitempty"`
-	Offset        int    `json:"offset,omitempty"`
-	ManifestIndex int    `json:"manifest_index,omitempty"`
-	SegmentIndex  int    `json:"segment_index,omitempty"`
+	Generation           string `json:"generation,omitempty"`
+	Origin               string `json:"origin,omitempty"`
+	KindIndex            int    `json:"kind_index,omitempty"`
+	Offset               int    `json:"offset,omitempty"`
+	SegmentIndex         int    `json:"segment_index,omitempty"`
+	PublicationSessionID string `json:"publication_session_id,omitempty"`
 }
 
 // OpenFolderTransport opens or initializes a marked artifact exchange target.
@@ -549,7 +549,6 @@ func validateFolderTransportState(state folderTransportPersistedState) error {
 	if state.PullSequence < 0 ||
 		push.KindIndex < 0 ||
 		push.Offset < 0 ||
-		push.ManifestIndex < 0 ||
 		push.SegmentIndex < 0 {
 		return errors.New("decoding artifact folder continuation state: negative cursor")
 	}